vendor/NetBSD/bmake/20240430

90 files changed, 388 insertions, 321 deletions

diff --git a/unit-tests/Makefile b/unit-tests/Makefile
index 6c41bf811dcf..5960a0621ddd 100644
--- a/unit-tests/Makefile
+++ b/unit-tests/Makefile
@@ -1,6 +1,6 @@
-# $Id: Makefile,v 1.211 2024/03/10 17:46:44 sjg Exp $
+# $Id: Makefile,v 1.216 2024/04/30 16:42:50 sjg Exp $
 #
-# $NetBSD: Makefile,v 1.342 2024/01/07 02:07:44 sjg Exp $
+# $NetBSD: Makefile,v 1.344 2024/04/30 16:41:32 sjg Exp $
 #
 # Unit tests for make(1)
 #
@@ -474,20 +474,11 @@ BROKEN_TESTS+= sh-flags
 BROKEN_TESTS+= varmod-localtime
 .endif
 
-.if ${.MAKE.OS:NCYGWIN*} == ""
-BROKEN_TESTS+= \
-	export \
-	opt-chdir \
-	opt-keep-going-indirect \
-
-.endif
-
-
 .if ${.MAKE.OS:NDarwin} == ""
 BROKEN_TESTS+= shell-ksh
 .endif
 
-.if ${.MAKE.OS:MIRIX*} != ""
+.if ${.MAKE.OS:NIRIX*} == ""
 BROKEN_TESTS+= \
 	cmd-interrupt \
 	deptgt-interrupt \
@@ -573,6 +564,9 @@ SED_CMDS.directive-include-guard= \
 	-e '/^ParseDependency/d' \
 	-e '/^ParseEOF:/d'
 SED_CMDS.export=	-e '/^[^=_A-Za-z0-9]*=/d'
+.if ${.MAKE.OS:NCygwin} == ""
+SED_CMDS.export+=	-e '/^WINDIR=/d' -e '/^SYSTEMROOT=/d'
+.endif
 SED_CMDS.export-all=	${SED_CMDS.export}
 SED_CMDS.export-env=	${SED_CMDS.export}
 SED_CMDS.cmdline=	-e 's,uid${.MAKE.UID}/,,'
@@ -625,7 +619,7 @@ SED_CMDS.var-op-shell+=		${STD_SED_CMDS.shell}
 SED_CMDS.var-op-shell+=		-e '/command/s,No such.*,not found,'
 SED_CMDS.var-op-shell+=		${STD_SED_CMDS.white-space}
 SED_CMDS.vardebug+=		-e 's,${.SHELL},</path/to/shell>,'
-SED_CMDS.varmod-mtime+=		-e "s,': .*,': <ENOENT>,"
+SED_CMDS.varmod-mtime+=		-e "s,\(.*\)': .*,\1': <ENOENT>,"
 SED_CMDS.varmod-subst-regex+=	${STD_SED_CMDS.regex}
 SED_CMDS.varparse-errors+=	${STD_SED_CMDS.timestamp}
 SED_CMDS.varname-dot-make-meta-ignore_filter+= ${SED_CMDS.meta-ignore}
@@ -655,8 +649,9 @@ unexport-env.rawout: export.mk
 
 # In tests that use the debugging option -dd, ignore debugging output that is
 # only logged in -DCLEANUP mode.
-STD_SED_CMDS.dd=		-e '/^OpenDirs_Done:/d'
-STD_SED_CMDS.dd+=		-e '/^CachedDir /d'
+STD_SED_CMDS.dd=	-e '/^OpenDirs_Done:/d'
+STD_SED_CMDS.dd+=	-e '/^CachedDir /d'
+STD_SED_CMDS.dd+=	-e 's,  ${DEFSYSPATH:U/usr/share/mk} ,  <defsyspath> ,'
 
 # Omit details such as process IDs from the output of the -dg1 option.
 STD_SED_CMDS.dg1=	-e '/\#.* \.$$/d'
@@ -762,12 +757,10 @@ TOOL_TR?=	tr
 TOOL_DIFF?=	diff
 DIFF_FLAGS?=	-u
 
-.if defined(.PARSEDIR)
 # ensure consistent results from sort(1)
 LC_ALL=		C
 LANG=		C
 .export LANG LC_ALL
-.endif
 
 .if ${.MAKE.MODE:Unormal:Mmeta} != ""
 # we don't need the noise
diff --git a/unit-tests/archive.exp b/unit-tests/archive.exp
index 645add4f5899..5cf847388544 100644
--- a/unit-tests/archive.exp
+++ b/unit-tests/archive.exp
@@ -25,4 +25,12 @@ depend-on-existing-member
 Making remove-archive
 rm -f libprog.a
 
+begin library
+Examining libbad.a...up-to-date.
+Examining -lbad...up-to-date.
+Examining libgood.a...library...up-to-date.
+Examining -lgood...library...up-to-date.
+Examining library...nonexistent....PHONY node...out-of-date.
+Examining .END...nonexistent...nonexistent and no sources...out-of-date.
+end library
 exit status 0
diff --git a/unit-tests/archive.mk b/unit-tests/archive.mk
index 2cd43a99e9ad..eef64396f419 100644
--- a/unit-tests/archive.mk
+++ b/unit-tests/archive.mk
@@ -1,4 +1,4 @@
-# $NetBSD: archive.mk,v 1.12 2021/04/09 14:42:00 christos Exp $
+# $NetBSD: archive.mk,v 1.13 2024/04/27 20:23:22 rillig Exp $
 #
 # Very basic demonstration of handling archives, based on the description
 # in PSD.doc/tutorial.ms.
@@ -24,6 +24,12 @@ all:
 	@${MAKE} -f ${MAKEFILE} depend-on-existing-member
 	@${MAKE} -f ${MAKEFILE} depend-on-nonexistent-member
 	@${MAKE} -f ${MAKEFILE} remove-archive
+	@${MAKE} -f ${MAKEFILE} set-up-library
+	@${MAKE} -f ${MAKEFILE} -dm library 2>&1 \
+	| sed -n '/^Examining/p' \
+	| sed 's,\.\.\.modified[^.]*,,'
+	@${MAKE} -f ${MAKEFILE} tear-down-library
+
 
 create-archive: ${ARCHIVE} pre post
 
@@ -58,3 +64,28 @@ pre: .USEBEFORE
 	@echo Making ${.TARGET} ${.OODATE:C,.+,out-of-date,W} ${.OODATE:O}
 post: .USE
 	@echo
+
+
+set-up-library: .PHONY
+	@echo "member" > member.txt
+	@echo "not a library" > libbad.a
+	@ar cr libgood.a member.txt
+	@echo "begin library"
+
+.if make(library)
+.SUFFIXES: .a
+.LIBS: .a
+.endif
+# The two lines for libgood contain the word "library", the two lines for
+# libbad don't.
+#
+# expect: Examining libbad.a...up-to-date.
+# expect: Examining -lbad...up-to-date.
+# expect: Examining libgood.a...library...up-to-date.
+# expect: Examining -lgood...library...up-to-date.
+library: .PHONY libbad.a -lbad libgood.a -lgood
+	: Making ${.TARGET} from ${.ALLSRC}
+
+tear-down-library: .PHONY
+	@echo "end library"
+	@rm member.txt libbad.a libgood.a
diff --git a/unit-tests/cmd-errors-jobs.exp b/unit-tests/cmd-errors-jobs.exp
index d0a6e51eb84d..c8e483a9609b 100644
--- a/unit-tests/cmd-errors-jobs.exp
+++ b/unit-tests/cmd-errors-jobs.exp
@@ -1,9 +1,9 @@
 : undefined--eol
-make: Unclosed variable "UNCLOSED"
-: unclosed-variable-
+make: in target "unclosed-expression": Unclosed variable "UNCLOSED"
+: unclosed-expression-
 make: Unclosed expression, expecting '}' for "UNCLOSED"
 : unclosed-modifier-
-make: Unknown modifier "Z"
+make: in target "unknown-modifier": while evaluating variable "UNKNOWN": Unknown modifier "Z"
 : unknown-modifier--eol
 : end-eol
 exit status 0
diff --git a/unit-tests/cmd-errors-jobs.mk b/unit-tests/cmd-errors-jobs.mk
index b3dc982de35f..7a82c0b416e8 100644
--- a/unit-tests/cmd-errors-jobs.mk
+++ b/unit-tests/cmd-errors-jobs.mk
@@ -1,32 +1,39 @@
-# $NetBSD: cmd-errors-jobs.mk,v 1.2 2022/09/25 12:51:37 rillig Exp $
+# $NetBSD: cmd-errors-jobs.mk,v 1.4 2024/04/23 22:51:28 rillig Exp $
 #
-# Demonstrate how errors in variable expansions affect whether the commands
+# Demonstrate how errors in expressions affect whether the commands
 # are actually executed in jobs mode.
 
 .MAKEFLAGS: -j1
 
-all: undefined unclosed-variable unclosed-modifier unknown-modifier end
+all: undefined unclosed-expression unclosed-modifier unknown-modifier end
 
-# Undefined variables are not an error.  They expand to empty strings.
+# Undefined variables in expressions are not an error.  They expand to empty
+# strings.
+# expect: : undefined--eol
 undefined:
 	: $@-${UNDEFINED}-eol
 
-# XXX: As of 2020-11-01, this command is executed even though it contains
-# parse errors.
-unclosed-variable:
+# XXX: This command is executed even though it contains parse errors.
+# expect: make: in target "unclosed-expression": Unclosed variable "UNCLOSED"
+# expect: : unclosed-expression-
+unclosed-expression:
 	: $@-${UNCLOSED
 
-# XXX: As of 2020-11-01, this command is executed even though it contains
-# parse errors.
+# XXX: This command is executed even though it contains parse errors.
+# expect: make: Unclosed expression, expecting '}' for "UNCLOSED"
+# expect: : unclosed-modifier-
 unclosed-modifier:
 	: $@-${UNCLOSED:
 
-# XXX: As of 2020-11-01, this command is executed even though it contains
-# parse errors.
+# XXX: This command is executed even though it contains parse errors.
+# expect: make: in target "unknown-modifier": while evaluating variable "UNKNOWN": Unknown modifier "Z"
+# expect: : unknown-modifier--eol
 unknown-modifier:
 	: $@-${UNKNOWN:Z}-eol
 
+# expect: : end-eol
 end:
 	: $@-eol
 
-# XXX: As of 2020-11-02, despite the parse errors, the exit status is 0.
+# XXX: Despite the parse errors, the exit status is 0.
+# expect: exit status 0
diff --git a/unit-tests/cmd-errors-lint.exp b/unit-tests/cmd-errors-lint.exp
index bdf4ae1a17e8..d489c6be57c9 100644
--- a/unit-tests/cmd-errors-lint.exp
+++ b/unit-tests/cmd-errors-lint.exp
@@ -1,9 +1,9 @@
 : undefined 
-make: Unclosed variable "UNCLOSED"
-: unclosed-variable 
+make: in target "unclosed-expression": Unclosed variable "UNCLOSED"
+: unclosed-expression 
 make: Unclosed expression, expecting '}' for "UNCLOSED"
 : unclosed-modifier 
-make: Unknown modifier "Z"
+make: in target "unknown-modifier": while evaluating variable "UNKNOWN": Unknown modifier "Z"
 : unknown-modifier 
 : end
 exit status 2
diff --git a/unit-tests/cmd-errors-lint.mk b/unit-tests/cmd-errors-lint.mk
index 371e12af0f4f..2e7d537f5f1f 100644
--- a/unit-tests/cmd-errors-lint.mk
+++ b/unit-tests/cmd-errors-lint.mk
@@ -1,20 +1,21 @@
-# $NetBSD: cmd-errors-lint.mk,v 1.1 2020/11/02 20:43:27 rillig Exp $
+# $NetBSD: cmd-errors-lint.mk,v 1.2 2024/04/23 22:51:28 rillig Exp $
 #
-# Demonstrate how errors in variable expansions affect whether the commands
+# Demonstrate how errors in expressions affect whether the commands
 # are actually executed.
 
 .MAKEFLAGS: -dL
 
-all: undefined unclosed-variable unclosed-modifier unknown-modifier end
+all: undefined unclosed-expression unclosed-modifier unknown-modifier end
 
-# Undefined variables are not an error.  They expand to empty strings.
+# Undefined variables in expressions are not an error.  They expand to empty
+# strings.
 undefined:
 	: $@ ${UNDEFINED}
 
 # XXX: As of 2020-11-01, this obvious syntax error is not detected.
 # XXX: As of 2020-11-01, this command is executed even though it contains
 # parse errors.
-unclosed-variable:
+unclosed-expression:
 	: $@ ${UNCLOSED
 
 # XXX: As of 2020-11-01, this obvious syntax error is not detected.
diff --git a/unit-tests/cmd-errors.exp b/unit-tests/cmd-errors.exp
index d0a6e51eb84d..c8e483a9609b 100644
--- a/unit-tests/cmd-errors.exp
+++ b/unit-tests/cmd-errors.exp
@@ -1,9 +1,9 @@
 : undefined--eol
-make: Unclosed variable "UNCLOSED"
-: unclosed-variable-
+make: in target "unclosed-expression": Unclosed variable "UNCLOSED"
+: unclosed-expression-
 make: Unclosed expression, expecting '}' for "UNCLOSED"
 : unclosed-modifier-
-make: Unknown modifier "Z"
+make: in target "unknown-modifier": while evaluating variable "UNKNOWN": Unknown modifier "Z"
 : unknown-modifier--eol
 : end-eol
 exit status 0
diff --git a/unit-tests/cmd-errors.mk b/unit-tests/cmd-errors.mk
index 6d3880684bcf..d1125d444fcd 100644
--- a/unit-tests/cmd-errors.mk
+++ b/unit-tests/cmd-errors.mk
@@ -1,17 +1,18 @@
-# $NetBSD: cmd-errors.mk,v 1.5 2022/09/25 12:51:37 rillig Exp $
+# $NetBSD: cmd-errors.mk,v 1.6 2024/04/23 22:51:28 rillig Exp $
 #
-# Demonstrate how errors in variable expansions affect whether the commands
+# Demonstrate how errors in expressions affect whether the commands
 # are actually executed in compat mode.
 
-all: undefined unclosed-variable unclosed-modifier unknown-modifier end
+all: undefined unclosed-expression unclosed-modifier unknown-modifier end
 
-# Undefined variables are not an error.  They expand to empty strings.
+# Undefined variables in expressions are not an error.  They expand to empty
+# strings.
 undefined:
 	: $@-${UNDEFINED}-eol
 
 # XXX: As of 2020-11-01, this command is executed even though it contains
 # parse errors.
-unclosed-variable:
+unclosed-expression:
 	: $@-${UNCLOSED
 
 # XXX: As of 2020-11-01, this command is executed even though it contains
diff --git a/unit-tests/cmdline-undefined.mk b/unit-tests/cmdline-undefined.mk
index 81b44518dd41..e7c0400ad1e1 100644
--- a/unit-tests/cmdline-undefined.mk
+++ b/unit-tests/cmdline-undefined.mk
@@ -1,6 +1,6 @@
-# $NetBSD: cmdline-undefined.mk,v 1.4 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: cmdline-undefined.mk,v 1.5 2024/04/23 22:51:28 rillig Exp $
 #
-# Tests for undefined expressions in the command line.
+# Tests for undefined variables in expressions in the command line.
 
 all:
 	# When the command line is parsed, variable assignments using the
diff --git a/unit-tests/cmdline.mk b/unit-tests/cmdline.mk
index a24d46208e52..40a0d7ccddbb 100644
--- a/unit-tests/cmdline.mk
+++ b/unit-tests/cmdline.mk
@@ -1,4 +1,4 @@
-# $NetBSD: cmdline.mk,v 1.4 2022/06/10 18:58:07 rillig Exp $
+# $NetBSD: cmdline.mk,v 1.5 2024/04/23 22:51:28 rillig Exp $
 #
 # Tests for command line parsing and related special variables.
 
@@ -24,7 +24,7 @@ makeobjdir-direct:
 	@${MAKE_CMD} MAKEOBJDIR=${DIR2} show-objdir
 
 # The .OBJDIR can be set via the MAKEOBJDIR command line variable,
-# and that variable could even contain the usual modifiers.
+# and expressions based on that variable can contain the usual modifiers.
 # Since the .OBJDIR=MAKEOBJDIR assignment happens very early,
 # the SUB2 variable in the modifier is not defined yet and is therefore empty.
 # The SUB1 in the resulting path comes from the environment variable TMPBASE,
diff --git a/unit-tests/comment.mk b/unit-tests/comment.mk
index a3bf781b9a67..fea0f0b3d817 100644
--- a/unit-tests/comment.mk
+++ b/unit-tests/comment.mk
@@ -1,4 +1,4 @@
-# $NetBSD: comment.mk,v 1.6 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: comment.mk,v 1.7 2024/04/23 22:51:28 rillig Exp $
 #
 # Demonstrate how comments are written in makefiles.
 
@@ -53,9 +53,9 @@ VAR=	\#		# Both in the assignment.
 .  error
 .endif
 
-# Since 2012-03-24 the variable modifier :[#] does not need to be escaped.
-# To keep the parsing code simple, any "[#" does not start a comment, even
-# outside of an expression.
+# Since 2012-03-24 the modifier :[#] does not need to be escaped.
+# To keep the parsing code simple, the "#" in "[#" does not start a comment,
+# regardless of the syntactical context it appears in.
 WORDS=	${VAR:[#]} [#
 .if ${WORDS} != "1 [#"
 .  error
diff --git a/unit-tests/cond-cmp-string.mk b/unit-tests/cond-cmp-string.mk
index 7b13ebf2212b..e3346e08b5a0 100644
--- a/unit-tests/cond-cmp-string.mk
+++ b/unit-tests/cond-cmp-string.mk
@@ -1,4 +1,4 @@
-# $NetBSD: cond-cmp-string.mk,v 1.18 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: cond-cmp-string.mk,v 1.19 2024/04/23 22:51:28 rillig Exp $
 #
 # Tests for string comparisons in .if conditions.
 
@@ -20,12 +20,12 @@
 .  error
 .endif
 
-# The left-hand side of the comparison requires that any expression
-# is defined.
+# An expression that occurs on the left-hand side of the comparison must be
+# defined.
 #
 # The variable named "" is never defined, nevertheless it can be used as a
-# starting point for expressions.  Applying the :U modifier to such
-# an undefined expression turns it into a defined expression.
+# starting point for an expression.  Applying the :U modifier to such an
+# undefined expression turns it into a defined expression.
 #
 # See ApplyModifier_Defined and DEF_DEFINED.
 .if ${:Ustr} != "str"
@@ -69,8 +69,9 @@
 .endif
 
 # Between 2003-01-01 (maybe even earlier) and 2020-10-30, adding one of the
-# characters " \t!=><" directly after an expression resulted in a
-# "Malformed conditional", even though the string was well-formed.
+# characters " \t!=><" directly after an expression in a string literal
+# resulted in a "Malformed conditional", even though the string was
+# well-formed.
 .if ${:Uword } != "${:Uword} "
 .  error
 .endif
@@ -94,8 +95,7 @@
 .  error
 .endif
 
-# Adding a space at the beginning of the quoted expression works
-# though.
+# Adding a space at the beginning of the quoted expression works though.
 .if ${:U word } != " ${:Uword} "
 .  error
 .endif
@@ -145,7 +145,7 @@
 .  error
 .endif
 
-# Two variables with different values compare unequal.
+# Two expressions with different values compare unequal.
 VAR1=	value1
 VAR2=	value2
 .if ${VAR1} != ${VAR2}
diff --git a/unit-tests/cond-func-defined.exp b/unit-tests/cond-func-defined.exp
index d556f3b982b3..1d4243f9eddd 100644
--- a/unit-tests/cond-func-defined.exp
+++ b/unit-tests/cond-func-defined.exp
@@ -1,8 +1,5 @@
 make: "cond-func-defined.mk" line 24: Missing closing parenthesis for defined()
 make: "cond-func-defined.mk" line 34: Missing closing parenthesis for defined()
-make: "cond-func-defined.mk" line 47: In .for loops, expressions for the loop variables are
-make: "cond-func-defined.mk" line 49: substituted at evaluation time.  There is no actual variable
-make: "cond-func-defined.mk" line 51: involved, even if it feels like it.
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
 exit status 1
diff --git a/unit-tests/cond-func-defined.mk b/unit-tests/cond-func-defined.mk
index 14597398bc62..6b24182c11c1 100644
--- a/unit-tests/cond-func-defined.mk
+++ b/unit-tests/cond-func-defined.mk
@@ -1,4 +1,4 @@
-# $NetBSD: cond-func-defined.mk,v 1.11 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: cond-func-defined.mk,v 1.12 2024/04/23 22:51:28 rillig Exp $
 #
 # Tests for the defined() function in .if conditions.
 
@@ -43,12 +43,9 @@ ${:UA B}=	variable name with spaces
 .  if defined(var)
 .    error
 .  else
-# expect+1: In .for loops, expressions for the loop variables are
-.    info In .for loops, expressions for the loop variables are
-# expect+1: substituted at evaluation time.  There is no actual variable
-.    info substituted at evaluation time.  There is no actual variable
-# expect+1: involved, even if it feels like it.
-.    info involved, even if it feels like it.
+# In .for loops, expressions based on the loop variables are substituted at
+# evaluation time.  There is no actual variable involved, even if the code in
+# the makefiles looks like it.
 .  endif
 .endfor
 
diff --git a/unit-tests/cond-token-string.exp b/unit-tests/cond-token-string.exp
index db07adcb2d09..4fbafc5e1986 100644
--- a/unit-tests/cond-token-string.exp
+++ b/unit-tests/cond-token-string.exp
@@ -1,4 +1,4 @@
-make: "cond-token-string.mk" line 15: Unknown modifier "Z"
+make: "cond-token-string.mk" line 15: while evaluating "${:Uvalue:Z}"": Unknown modifier "Z"
 make: "cond-token-string.mk" line 15: Malformed conditional ("" != "${:Uvalue:Z}")
 make: "cond-token-string.mk" line 25: xvalue is not defined.
 make: "cond-token-string.mk" line 32: Malformed conditional (x${:Uvalue} == "")
diff --git a/unit-tests/cond-token-string.mk b/unit-tests/cond-token-string.mk
index d13c68da134a..edc9936b7d53 100644
--- a/unit-tests/cond-token-string.mk
+++ b/unit-tests/cond-token-string.mk
@@ -1,4 +1,4 @@
-# $NetBSD: cond-token-string.mk,v 1.9 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: cond-token-string.mk,v 1.10 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for quoted string literals in .if conditions.
 #
@@ -11,7 +11,7 @@
 # Cover the code in CondParser_String that frees the memory after parsing
 # an expression based on an undefined variable.
 # expect+2: Malformed conditional ("" != "${:Uvalue:Z}")
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating "${:Uvalue:Z}"": Unknown modifier "Z"
 .if "" != "${:Uvalue:Z}"
 .  error
 .else
diff --git a/unit-tests/depsrc-end.mk b/unit-tests/depsrc-end.mk
index eb7543d5dfad..1bfe50d98620 100644
--- a/unit-tests/depsrc-end.mk
+++ b/unit-tests/depsrc-end.mk
@@ -1,6 +1,6 @@
-# $NetBSD: depsrc-end.mk,v 1.1 2020/10/23 19:23:01 rillig Exp $
+# $NetBSD: depsrc-end.mk,v 1.2 2024/04/27 20:41:32 rillig Exp $
 #
-# Demonstrate the edge case that .BEGIN depends on .END, which sounds a bit
+# Demonstrate an edge case in which .BEGIN depends on .END, which sounds a bit
 # paradox but works since these special nodes are not in the dependency
 # hierarchy where the cycles are detected.
 
diff --git a/unit-tests/depsrc-nopath.exp b/unit-tests/depsrc-nopath.exp
index 39a9383953dd..01295d8df7f5 100644
--- a/unit-tests/depsrc-nopath.exp
+++ b/unit-tests/depsrc-nopath.exp
@@ -1 +1,3 @@
+: Making test-regular from depsrc-nopath.dir/regular.file
+: Making test-nopath from nopath.file
 exit status 0
diff --git a/unit-tests/depsrc-nopath.mk b/unit-tests/depsrc-nopath.mk
index 052c6f10db66..8d9ce93c16b9 100644
--- a/unit-tests/depsrc-nopath.mk
+++ b/unit-tests/depsrc-nopath.mk
@@ -1,8 +1,27 @@
-# $NetBSD: depsrc-nopath.mk,v 1.2 2020/08/16 14:25:16 rillig Exp $
+# $NetBSD: depsrc-nopath.mk,v 1.3 2024/04/27 20:41:32 rillig Exp $
 #
 # Tests for the special source .NOPATH in dependency declarations.
 
-# TODO: Implementation
+.if !target(test-*)
+_!=	rm -rf depsrc-nopath.dir
+_!=	mkdir depsrc-nopath.dir
+_!=	touch depsrc-nopath.dir/regular.file
+_!=	touch depsrc-nopath.dir/nopath.file
+.endif
 
 all:
-	@:;
+	@${MAKE} -f ${MAKEFILE} test-regular
+	@${MAKE} -f ${MAKEFILE} test-nopath || echo "should have failed"
+	@rm -rf depsrc-nopath.dir
+
+.PATH: depsrc-nopath.dir
+
+test-regular: regular.file
+	: Making ${.TARGET} from ${.ALLSRC}
+test-nopath: nopath.file
+	: Making ${.TARGET} from ${.ALLSRC}
+
+nopath.file: .NOPATH
+
+# expect: : Making test-regular from depsrc-nopath.dir/regular.file
+# expect: : Making test-nopath from nopath.file
diff --git a/unit-tests/depsrc-phony.mk b/unit-tests/depsrc-phony.mk
index c41efac369a8..9df1eb570ab4 100644
--- a/unit-tests/depsrc-phony.mk
+++ b/unit-tests/depsrc-phony.mk
@@ -1,9 +1,10 @@
-# $NetBSD: depsrc-phony.mk,v 1.3 2020/09/05 15:57:12 rillig Exp $
+# $NetBSD: depsrc-phony.mk,v 1.4 2024/04/27 20:41:32 rillig Exp $
 #
 # Tests for the special source .PHONY in dependency declarations,
 # which executes the commands for the target even if a file of the same
 # name exists and would be considered up to date.
 
 # Without the .PHONY, this target would be "up to date".
+# expect: : depsrc-phony.mk is made.
 ${MAKEFILE}: .PHONY
 	: ${.TARGET:T} is made.
diff --git a/unit-tests/deptgt-phony.exp b/unit-tests/deptgt-phony.exp
index 1c379b32a33b..e943091e4cef 100644
--- a/unit-tests/deptgt-phony.exp
+++ b/unit-tests/deptgt-phony.exp
@@ -2,7 +2,7 @@ Expanding "depsrc-phony-pr-15164-*-wildcard"...
 Expanding "deptgt-phony-pr-15164-*-wildcard"... 
 Searching for .depend ...
    failed.
-Searching for .depend ...
+Searching for .depend ...[dot last]...
    . ...
    failed.
 Wildcard expanding "all"...
diff --git a/unit-tests/deptgt.exp b/unit-tests/deptgt.exp
index 00d312685de9..90213fe44fb5 100644
--- a/unit-tests/deptgt.exp
+++ b/unit-tests/deptgt.exp
@@ -8,7 +8,7 @@ ParseDependency(: empty-source)
 Parsing line 39: 	: command for empty targets list
 Parsing line 40: .MAKEFLAGS: -d0
 ParseDependency(.MAKEFLAGS: -d0)
-make: "deptgt.mk" line 49: Unknown modifier "Z"
+make: "deptgt.mk" line 49: while evaluating "${:U:Z}:": Unknown modifier "Z"
 make: "deptgt.mk" line 52: warning: Extra target 'ordinary' ignored
 make: "deptgt.mk" line 55: warning: Extra target (ordinary) ignored
 make: "deptgt.mk" line 58: warning: Special and mundane targets don't mix. Mundane ones ignored
diff --git a/unit-tests/deptgt.mk b/unit-tests/deptgt.mk
index 30b8399191bd..eb948918abb7 100644
--- a/unit-tests/deptgt.mk
+++ b/unit-tests/deptgt.mk
@@ -1,4 +1,4 @@
-# $NetBSD: deptgt.mk,v 1.16 2023/12/17 09:44:00 rillig Exp $
+# $NetBSD: deptgt.mk,v 1.17 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for special targets like .BEGIN or .SUFFIXES in dependency
 # declarations.
@@ -45,7 +45,7 @@ ${:U}: empty-source
 # expansion would be to use the variable modifier '::=' to modify the
 # targets.  This in turn would be such an extreme and unreliable edge case
 # that nobody uses it.
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating "${:U:Z}:": Unknown modifier "Z"
 $$$$$$$${:U:Z}:
 
 # expect+1: warning: Extra target 'ordinary' ignored
diff --git a/unit-tests/directive-export-impl.exp b/unit-tests/directive-export-impl.exp
index fada441f5e92..7daf1f45b0cb 100644
--- a/unit-tests/directive-export-impl.exp
+++ b/unit-tests/directive-export-impl.exp
@@ -10,6 +10,7 @@ Pattern for ':N' is "*"
 ModifyWords: split "<>" into 1 word
 Result of ${UT_VAR:N*} is ""
 ParseDependency(: )
+Parsing line 42: .if ${:!echo "\$UT_VAR"!} != "<>"
 CondParser_Eval: ${:!echo "\$UT_VAR"!} != "<>"
 Var_Parse: ${:!echo "\$UT_VAR"!} != "<>" (eval-defined)
 Evaluating modifier ${:!...} on value "" (eval-defined, undefined)
@@ -34,6 +35,7 @@ Result of ${UT_VAR:N*} is ""
 ParseDependency(: )
 Parsing line 54: REF=		defined
 Global: REF = defined
+Parsing line 58: .if ${:!echo "\$UT_VAR"!} != "<defined>"
 CondParser_Eval: ${:!echo "\$UT_VAR"!} != "<defined>"
 Var_Parse: ${:!echo "\$UT_VAR"!} != "<defined>" (eval-defined)
 Evaluating modifier ${:!...} on value "" (eval-defined, undefined)
diff --git a/unit-tests/directive-for-errors.exp b/unit-tests/directive-for-errors.exp
index 115a6af5b069..9c1aa5c0b1ed 100644
--- a/unit-tests/directive-for-errors.exp
+++ b/unit-tests/directive-for-errors.exp
@@ -8,7 +8,7 @@ make: "directive-for-errors.mk" line 44: invalid character '$' in .for loop vari
 make: "directive-for-errors.mk" line 52: no iteration variables in for
 make: "directive-for-errors.mk" line 64: Wrong number of words (5) in .for substitution list with 3 variables
 make: "directive-for-errors.mk" line 78: missing `in' in for
-make: "directive-for-errors.mk" line 89: Unknown modifier "Z"
+make: "directive-for-errors.mk" line 89: while evaluating "${:U3:Z} 4": Unknown modifier "Z"
 make: "directive-for-errors.mk" line 90: warning: Should not be reached.
 make: "directive-for-errors.mk" line 90: warning: Should not be reached.
 make: "directive-for-errors.mk" line 90: warning: Should not be reached.
diff --git a/unit-tests/directive-for-errors.mk b/unit-tests/directive-for-errors.mk
index 94362847cdfd..1bd4f31d383a 100644
--- a/unit-tests/directive-for-errors.mk
+++ b/unit-tests/directive-for-errors.mk
@@ -1,4 +1,4 @@
-# $NetBSD: directive-for-errors.mk,v 1.9 2023/12/19 19:33:40 rillig Exp $
+# $NetBSD: directive-for-errors.mk,v 1.10 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for error handling in .for loops.
 
@@ -85,7 +85,7 @@ ${:U\\}=	backslash	# see whether the "variable" '\' is local
 #
 # XXX: As of 2020-12-31, Var_Subst doesn't report any errors, therefore
 # the loop body is expanded as if no error had happened.
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating "${:U3:Z} 4": Unknown modifier "Z"
 .for i in 1 2 ${:U3:Z} 4
 .  warning Should not be reached.
 .endfor
diff --git a/unit-tests/directive-for-escape.exp b/unit-tests/directive-for-escape.exp
index 6c84b7780e84..1f4305185d65 100644
--- a/unit-tests/directive-for-escape.exp
+++ b/unit-tests/directive-for-escape.exp
@@ -106,6 +106,7 @@ make: "directive-for-escape.mk" line 228: long: " "
 For: end for 1
 For: loop body with i = "
 ":
+Parsing line 244: .for i in "${.newline}"
 For: end for 1
 Parse_PushInput: .for loop in directive-for-escape.mk, line 244
 make: "directive-for-escape.mk" line 244: newline in .for value
diff --git a/unit-tests/directive-for-null.exp b/unit-tests/directive-for-null.exp
index dee26de25e63..d6198c644817 100644
--- a/unit-tests/directive-for-null.exp
+++ b/unit-tests/directive-for-null.exp
@@ -1,9 +1,5 @@
 make: "(stdin)" line 2: Zero byte read from file
-make: "(stdin)" line 2: Unexpected end of file in .for loop
-make: "(stdin)" line 3: Zero byte read from file
-make: Fatal errors encountered -- cannot continue
-make: stopped in unit-tests
-*** Error code 1 (continuing)
+*** Error code 2 (continuing)
 
 Stop.
 make: stopped in unit-tests
diff --git a/unit-tests/directive-for-null.mk b/unit-tests/directive-for-null.mk
index fb2d440ee1ba..d3de8b598bc2 100644
--- a/unit-tests/directive-for-null.mk
+++ b/unit-tests/directive-for-null.mk
@@ -1,18 +1,8 @@
-# $NetBSD: directive-for-null.mk,v 1.3 2022/06/12 15:03:27 rillig Exp $
+# $NetBSD: directive-for-null.mk,v 1.4 2024/04/01 12:26:02 rillig Exp $
 #
 # Test for parsing a .for loop that accidentally contains a null byte.
 #
-# As of 2020-12-19, there are 3 error messages:
-#
-#	make: "(stdin)" line 2: Zero byte read from file
-#	make: "(stdin)" line 2: Unexpected end of file in for loop.
-#	make: "(stdin)" line 3: Zero byte read from file
-#
-# The one about "end of file" might be misleading but is due to the
-# implementation.  On both errors and EOF, ParseRawLine returns NULL.
-#
-# The one about the "zero byte" in line 3 is surprising since the only
-# line that contains a null byte is line 2.
+# expect: make: "(stdin)" line 2: Zero byte read from file
 
 all: .PHONY
 	@printf '%s\n' \
diff --git a/unit-tests/directive-for.exp b/unit-tests/directive-for.exp
index 0d0313c4e7b0..3e346dfab4ea 100755
--- a/unit-tests/directive-for.exp
+++ b/unit-tests/directive-for.exp
@@ -17,7 +17,7 @@ make: "directive-for.mk" line 146: }{ }{ }{
 make: "directive-for.mk" line 166: invalid character ':' in .for loop variable name
 make: "directive-for.mk" line 173: invalid character '$' in .for loop variable name
 make: "directive-for.mk" line 185: invalid character '$' in .for loop variable name
-make: "directive-for.mk" line 210: Unknown modifier "Z"
+make: "directive-for.mk" line 210: while evaluating "${:Uword2:Z}-after word3": Unknown modifier "Z"
 make: "directive-for.mk" line 211: XXX: Should not reach word1
 make: "directive-for.mk" line 211: XXX: Should not reach before--after
 make: "directive-for.mk" line 211: XXX: Should not reach word3
diff --git a/unit-tests/directive-for.mk b/unit-tests/directive-for.mk
index becc314226dc..d777c3921556 100755
--- a/unit-tests/directive-for.mk
+++ b/unit-tests/directive-for.mk
@@ -1,4 +1,4 @@
-# $NetBSD: directive-for.mk,v 1.24 2023/12/06 22:28:20 rillig Exp $
+# $NetBSD: directive-for.mk,v 1.25 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the .for directive.
 #
@@ -206,7 +206,7 @@ INDIRECT=	${DIRECT}
 # XXX: A parse error or evaluation error in the items of the .for loop
 # should skip the whole loop.  As of 2023-05-09, the loop is expanded as
 # usual.
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating "${:Uword2:Z}-after word3": Unknown modifier "Z"
 .for var in word1 before-${:Uword2:Z}-after word3
 .  info XXX: Should not reach ${var}
 .endfor
diff --git a/unit-tests/directive-include.exp b/unit-tests/directive-include.exp
index de94b751b33a..6454b6835edf 100755
--- a/unit-tests/directive-include.exp
+++ b/unit-tests/directive-include.exp
@@ -4,7 +4,7 @@ CondParser_Eval: ${.MAKE.MAKEFILES:T} != "${.PARSEFILE} null"
 Comparing "directive-include.mk null" != "directive-include.mk null"
 make: "directive-include.mk" line 26: Could not find nonexistent.mk
 make: "directive-include.mk" line 49: Could not find "
-make: "directive-include.mk" line 56: Unknown modifier "Z"
+make: "directive-include.mk" line 56: while evaluating "${:U123:Z}.mk": Unknown modifier "Z"
 make: "directive-include.mk" line 56: Could not find nonexistent.mk
 make: "directive-include.mk" line 61: Cannot open /nonexistent
 make: "directive-include.mk" line 66: Invalid line 'include'
diff --git a/unit-tests/directive-include.mk b/unit-tests/directive-include.mk
index 2517b4be6930..14d00600cb8f 100755
--- a/unit-tests/directive-include.mk
+++ b/unit-tests/directive-include.mk
@@ -1,4 +1,4 @@
-# $NetBSD: directive-include.mk,v 1.13 2023/08/19 10:52:14 rillig Exp $
+# $NetBSD: directive-include.mk,v 1.14 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the .include directive, which includes another file.
 
@@ -52,7 +52,7 @@ DQUOT=	"
 # expression is skipped and the file is included nevertheless.
 # FIXME: Add proper error handling, no file must be included here.
 # expect+2: Could not find nonexistent.mk
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating "${:U123:Z}.mk": Unknown modifier "Z"
 .include "nonexistent${:U123:Z}.mk"
 
 # The traditional include directive is seldom used.
diff --git a/unit-tests/directive-undef.exp b/unit-tests/directive-undef.exp
index f3957a990e18..329dc8d6282a 100644
--- a/unit-tests/directive-undef.exp
+++ b/unit-tests/directive-undef.exp
@@ -1,5 +1,5 @@
 make: "directive-undef.mk" line 30: The .undef directive requires an argument
-make: "directive-undef.mk" line 88: Unknown modifier "Z"
+make: "directive-undef.mk" line 88: while evaluating variable "VARNAMES": Unknown modifier "Z"
 make: "directive-undef.mk" line 105: warning: UT_EXPORTED is still listed in .MAKE.EXPORTED even though spaceit is not exported anymore.
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/directive-undef.mk b/unit-tests/directive-undef.mk
index ef047fefe177..ac4b20d3e858 100644
--- a/unit-tests/directive-undef.mk
+++ b/unit-tests/directive-undef.mk
@@ -1,4 +1,4 @@
-# $NetBSD: directive-undef.mk,v 1.13 2023/06/01 20:56:35 rillig Exp $
+# $NetBSD: directive-undef.mk,v 1.14 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the .undef directive.
 #
@@ -84,7 +84,7 @@ ${DOLLAR}=	dollar
 #
 # As of var.c 1.762, this doesn't happen though because the error handling
 # in Var_Parse and Var_Subst is not done properly.
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating variable "VARNAMES": Unknown modifier "Z"
 .undef ${VARNAMES:L:Z}
 
 
diff --git a/unit-tests/lint.exp b/unit-tests/lint.exp
index db2290c040cd..78761c862298 100755
--- a/unit-tests/lint.exp
+++ b/unit-tests/lint.exp
@@ -1,4 +1,4 @@
-make: In the :@ modifier of "VAR", the variable name "${:Ubar:S,b,v,}" must not contain a dollar
+make: in target "mod-loop-varname": while evaluating variable "VAR": In the :@ modifier, the variable name "${:Ubar:S,b,v,}" must not contain a dollar
 y@:Q}
 xvaluey
 exit status 2
diff --git a/unit-tests/moderrs.exp b/unit-tests/moderrs.exp
index 6b41241b6800..0d1bcdc5b0f9 100644
--- a/unit-tests/moderrs.exp
+++ b/unit-tests/moderrs.exp
@@ -1,11 +1,11 @@
 mod-unknown-direct:
 want: Unknown modifier 'Z'
-make: Unknown modifier "Z"
+make: in target "mod-unknown-direct": while evaluating variable "VAR": Unknown modifier "Z"
 VAR:Z=before--after
 
 mod-unknown-indirect:
 want: Unknown modifier 'Z'
-make: Unknown modifier "Z"
+make: in target "mod-unknown-indirect": while evaluating variable "VAR": Unknown modifier "Z"
 VAR:Z=before-inner}-after
 
 unclosed-direct:
@@ -119,17 +119,17 @@ then
 
 mod-remember-parse:
 1 1 2 3 5 8 13 21 34
-make: Unknown modifier "__"
+make: in target "mod-remember-parse": while evaluating variable "FIB": Unknown modifier "__"
 
 
 mod-sysv-parse:
-make: Unknown modifier "3"
+make: in target "mod-sysv-parse": while evaluating variable "FIB": Unknown modifier "3"
 make: Unclosed expression, expecting '}' for modifier "3" of variable "FIB" with value ""
 
-make: Unknown modifier "3="
+make: in target "mod-sysv-parse": while evaluating variable "FIB": Unknown modifier "3="
 make: Unclosed expression, expecting '}' for modifier "3=" of variable "FIB" with value ""
 
-make: Unknown modifier "3=x3"
+make: in target "mod-sysv-parse": while evaluating variable "FIB": Unknown modifier "3=x3"
 make: Unclosed expression, expecting '}' for modifier "3=x3" of variable "FIB" with value ""
 
 1 1 2 x3 5 8 1x3 21 34
diff --git a/unit-tests/opt-chdir.exp b/unit-tests/opt-chdir.exp
index d9759cf9ed8b..3d89360f9a62 100644
--- a/unit-tests/opt-chdir.exp
+++ b/unit-tests/opt-chdir.exp
@@ -1,5 +1,3 @@
-make: chdir /./././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././././.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 File name too long
-*** Error code 2 (ignored)
 cwd: /
 make: chdir /nonexistent: No such file or directory
 *** Error code 2 (ignored)
diff --git a/unit-tests/opt-chdir.mk b/unit-tests/opt-chdir.mk
index a8806149f31c..e94b8799af2e 100644
--- a/unit-tests/opt-chdir.mk
+++ b/unit-tests/opt-chdir.mk
@@ -1,4 +1,4 @@
-# $NetBSD: opt-chdir.mk,v 1.6 2021/05/18 17:05:45 sjg Exp $
+# $NetBSD: opt-chdir.mk,v 1.7 2024/04/02 11:11:00 rillig Exp $
 #
 # Tests for the -C command line option, which changes the directory at the
 # beginning.
@@ -7,15 +7,9 @@
 
 .MAKEFLAGS: -d0			# switch stdout to line-buffered
 
-all: chdir-filename-too-long
 all: chdir-root
 all: chdir-nonexistent
 
-# Try to overflow the internal buffer for .CURDIR, which is curdir.
-chdir-filename-too-long: .PHONY .IGNORE
-	# 5000 slashes, separated by dots: /./././.../././
-	@${MAKE} -C ${:U:range=5000:@@/@:ts.}
-
 # Changing to another directory is possible via the command line.
 # In this test, it is the root directory since almost any other directory
 # is not guaranteed to exist on every platform.
diff --git a/unit-tests/opt-debug-errors-jobs.exp b/unit-tests/opt-debug-errors-jobs.exp
index c957c7736b32..614bb33b9208 100644
--- a/unit-tests/opt-debug-errors-jobs.exp
+++ b/unit-tests/opt-debug-errors-jobs.exp
@@ -2,6 +2,7 @@ echo '3   spaces'; false
 3   spaces
 
 *** Failed target: fail-spaces
+*** In directory: <curdir>
 *** Failed commands:
 	echo '3   spaces'; false
 *** [fail-spaces] Error code 1
@@ -11,6 +12,7 @@ echo \  indented; false
   indented
 
 *** Failed target: fail-escaped-space
+*** In directory: <curdir>
 *** Failed commands:
 	echo \  indented; false
 *** [fail-escaped-space] Error code 1
@@ -22,6 +24,7 @@ line1
 line2
 
 *** Failed target: fail-newline
+*** In directory: <curdir>
 *** Failed commands:
 	echo 'line1${.newline}line2'; false
 	=> echo 'line1
@@ -33,6 +36,7 @@ echo 'line1 line2'; false
 line1 line2
 
 *** Failed target: fail-multiline
+*** In directory: <curdir>
 *** Failed commands:
 	echo 'line1 line2'; false
 *** [fail-multiline] Error code 1
@@ -42,6 +46,7 @@ echo	'word1'							 'word2'; false
 word1 word2
 
 *** Failed target: fail-multiline-intention
+*** In directory: <curdir>
 *** Failed commands:
 	echo	'word1'							 'word2'; false
 *** [fail-multiline-intention] Error code 1
@@ -49,6 +54,7 @@ word1 word2
 make: stopped in unit-tests
 
 *** Failed target: fail-vars
+*** In directory: <curdir>
 *** Failed commands:
 	@${COMPILE_C} ${COMPILE_C_FLAGS}
 	=> @false c-compiler flag1 -macro="several words"
diff --git a/unit-tests/opt-debug-lint.exp b/unit-tests/opt-debug-lint.exp
index 5a6510bd029a..c6cd748acd5d 100644
--- a/unit-tests/opt-debug-lint.exp
+++ b/unit-tests/opt-debug-lint.exp
@@ -2,9 +2,9 @@ make: "opt-debug-lint.mk" line 21: Variable "X" is undefined
 make: "opt-debug-lint.mk" line 21: Malformed conditional ($X)
 make: "opt-debug-lint.mk" line 45: Variable "UNDEF" is undefined
 make: "opt-debug-lint.mk" line 45: Malformed conditional (${UNDEF})
-make: "opt-debug-lint.mk" line 67: Missing delimiter ':' after modifier "L"
-make: "opt-debug-lint.mk" line 67: Missing delimiter ':' after modifier "P"
-make: "opt-debug-lint.mk" line 76: Unknown modifier "${"
+make: "opt-debug-lint.mk" line 67: while evaluating variable "value": Missing delimiter ':' after modifier "L"
+make: "opt-debug-lint.mk" line 67: while evaluating variable "value": Missing delimiter ':' after modifier "P"
+make: "opt-debug-lint.mk" line 76: while evaluating variable "value": Unknown modifier "${"
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
 exit status 1
diff --git a/unit-tests/opt-debug-lint.mk b/unit-tests/opt-debug-lint.mk
index 042bfd51d35b..3e946ac6ad61 100644
--- a/unit-tests/opt-debug-lint.mk
+++ b/unit-tests/opt-debug-lint.mk
@@ -1,4 +1,4 @@
-# $NetBSD: opt-debug-lint.mk,v 1.16 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: opt-debug-lint.mk,v 1.17 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the -dL command line option, which runs additional checks
 # to catch common mistakes, such as unclosed expressions.
@@ -62,8 +62,8 @@ ${UNDEF}: ${UNDEF}
 
 # Since 2020-10-03, in lint mode the variable modifier must be separated
 # by colons.  See varparse-mod.mk.
-# expect+2: Missing delimiter ':' after modifier "L"
-# expect+1: Missing delimiter ':' after modifier "P"
+# expect+2: while evaluating variable "value": Missing delimiter ':' after modifier "L"
+# expect+1: while evaluating variable "value": Missing delimiter ':' after modifier "P"
 .if ${value:LPL} != "value"
 .  error
 .endif
@@ -72,7 +72,7 @@ ${UNDEF}: ${UNDEF}
 # variable modifier had to be separated by colons.  This was wrong though
 # since make always fell back trying to parse the indirect modifier as a
 # SysV modifier.
-# expect+1: Unknown modifier "${"
+# expect+1: while evaluating variable "value": Unknown modifier "${"
 .if ${value:${:UL}PL} != "LPL}"		# FIXME: "LPL}" is unexpected here.
 .  error ${value:${:UL}PL}
 .endif
diff --git a/unit-tests/opt-debug-parse.exp b/unit-tests/opt-debug-parse.exp
index 811c6b45dce5..a19a58bcc965 100644
--- a/unit-tests/opt-debug-parse.exp
+++ b/unit-tests/opt-debug-parse.exp
@@ -1,3 +1,4 @@
+Parsing line 16: .for  var  in  value
 Parse_PushInput: .for loop in opt-debug-parse.mk, line 16
 SetFilenameVars: ${.PARSEDIR} = <some-dir> ${.PARSEFILE} = `opt-debug-parse.mk'
 Parsing line 21: .info trace with multi-line .for loop head
@@ -11,6 +12,7 @@ SetFilenameVars: ${.PARSEDIR} = <some-dir> ${.PARSEFILE} = `null'
 SetFilenameVars: ${.INCLUDEDFROMDIR} = <some-dir> ${.INCLUDEDFROMFILE} = `opt-debug-parse.mk'
 ParseEOF: returning to file opt-debug-parse.mk, line 27
 SetFilenameVars: ${.PARSEDIR} = <some-dir> ${.PARSEFILE} = `opt-debug-parse.mk'
+Parsing line 31: .for a b c in 1 2 3 ${:U4 5 6}
 Parse_PushInput: .for loop in opt-debug-parse.mk, line 31
 SetFilenameVars: ${.PARSEDIR} = <some-dir> ${.PARSEFILE} = `opt-debug-parse.mk'
 Parsing line 34: .info trace
diff --git a/unit-tests/opt-file.exp b/unit-tests/opt-file.exp
index 76a832949aca..9550958fea37 100644
--- a/unit-tests/opt-file.exp
+++ b/unit-tests/opt-file.exp
@@ -2,9 +2,7 @@ value
 value
 line-with-trailing-whitespace
 make: "(stdin)" line 1: Zero byte read from file
-make: Fatal errors encountered -- cannot continue
-make: stopped in unit-tests
-*** Error code 1 (continuing)
+*** Error code 2 (continuing)
 `all' not remade because of errors.
 
 Stop.
diff --git a/unit-tests/opt-file.mk b/unit-tests/opt-file.mk
index 5085fe126af8..0f07ede560f5 100644
--- a/unit-tests/opt-file.mk
+++ b/unit-tests/opt-file.mk
@@ -1,4 +1,4 @@
-# $NetBSD: opt-file.mk,v 1.15 2022/03/26 13:32:31 rillig Exp $
+# $NetBSD: opt-file.mk,v 1.16 2024/04/01 12:26:02 rillig Exp $
 #
 # Tests for the -f command line option, which adds a makefile to the list of
 # files that are parsed.
@@ -79,7 +79,7 @@ line-with-trailing-whitespace: .PHONY
 #	exit status 0
 #
 #	2008 to 2010:
-#	make: "zero-byte.in" line 1: Zero byte read from file
+#	make: "(stdin)" line 1: Zero byte read from file
 #	make: Fatal errors encountered -- cannot continue
 #
 #	make: stopped in .
@@ -92,14 +92,18 @@ line-with-trailing-whitespace: .PHONY
 #	exit status 2
 #
 #	2014 to 2020-12-06:
-#	make: "zero-byte.in" line 1: warning: Zero byte read from file, skipping rest of line.
+#	make: "(stdin)" line 1: warning: Zero byte read from file, skipping rest of line.
 #	exit status 0
 #
 #	Since 2020-12-07:
-#	make: "zero-byte.in" line 1: Zero byte read from file
+#	make: "(stdin)" line 1: Zero byte read from file
 #	make: Fatal errors encountered -- cannot continue
 #	make: stopped in .
 #	exit status 1
+#
+#	Since 2024-04-01:
+#	make: "(stdin)" line 1: Zero byte read from file
+#	*** Error code 2 (continuing)
 file-containing-null-byte: .PHONY
 	@printf '%s\n' 'VAR=value' 'VAR2=VALUE2' \
 	| tr 'l' '\0' \
diff --git a/unit-tests/opt-keep-going-indirect.mk b/unit-tests/opt-keep-going-indirect.mk
index 22f7be945f71..5d18553fa512 100644
--- a/unit-tests/opt-keep-going-indirect.mk
+++ b/unit-tests/opt-keep-going-indirect.mk
@@ -1,4 +1,4 @@
-# $NetBSD: opt-keep-going-indirect.mk,v 1.2 2022/02/12 20:05:36 rillig Exp $
+# $NetBSD: opt-keep-going-indirect.mk,v 1.3 2024/04/02 15:05:15 rillig Exp $
 #
 # Tests for the -k command line option, which stops building a target as soon
 # as an error is detected, but continues building the other, independent
@@ -49,19 +49,19 @@
 # to the child processes.
 all:
 	@echo 'direct compat'
-	@set +e; env -i ${MAKE} -r -f ${MAKEFILE} -k direct; echo "exited $$?"
+	@set +e; env -i "PATH=$$PATH" ${MAKE} -r -f ${MAKEFILE} -k direct; echo "exited $$?"
 	@echo
 
 	@echo 'direct jobs'
-	@set +e; env -i ${MAKE} -r -f ${MAKEFILE} -k direct -j1; echo "exited $$?"
+	@set +e; env -i "PATH=$$PATH" ${MAKE} -r -f ${MAKEFILE} -k direct -j1; echo "exited $$?"
 	@echo
 
 	@echo 'indirect compat'
-	@set +e; env -i ${MAKE} -r -f ${MAKEFILE} -k indirect; echo "exited $$?"
+	@set +e; env -i "PATH=$$PATH" ${MAKE} -r -f ${MAKEFILE} -k indirect; echo "exited $$?"
 	@echo
 
 	@echo 'indirect jobs'
-	@set +e; env -i ${MAKE} -r -f ${MAKEFILE} -k indirect -j1; echo "exited $$?"
+	@set +e; env -i "PATH=$$PATH" ${MAKE} -r -f ${MAKEFILE} -k indirect -j1; echo "exited $$?"
 	@echo
 
 indirect: direct
diff --git a/unit-tests/opt-m-include-dir.mk b/unit-tests/opt-m-include-dir.mk
index 6e0801390395..b677f172e85b 100644
--- a/unit-tests/opt-m-include-dir.mk
+++ b/unit-tests/opt-m-include-dir.mk
@@ -1,4 +1,4 @@
-# $NetBSD: opt-m-include-dir.mk,v 1.4 2020/09/01 20:14:34 rillig Exp $
+# $NetBSD: opt-m-include-dir.mk,v 1.5 2024/04/30 16:13:34 sjg Exp $
 #
 # Tests for the -m command line option, which adds a directory to the
 # search path for the .include <...> directive.
@@ -22,11 +22,14 @@
 TEST_DIR:=	${.PARSEFILE:R}.tmp/sub/sub/sub/workdir
 CANARY_FILE:=	${.PARSEFILE:R}.tmp/sub/opt-m-canary.mk
 ACTUAL_FILE:=	${.PARSEFILE:R}.tmp/sub/opt-m-step3.mk
+WANTED_FILE:=	${.PARSEFILE:R}.tmp/sub/opt-m-check.mk
 
 _!=	mkdir -p ${TEST_DIR}
 _!=	> ${CANARY_FILE}
 _!=	cp ${MAKEFILE} ${TEST_DIR}/step2.mk
 _!=	cp ${MAKEFILE} ${ACTUAL_FILE}
+_!=	echo CHECK=ok > ${WANTED_FILE}
+_!=	echo CHECK=${WANTED_FILE:T} found in .CURDIR > ${TEST_DIR}/${WANTED_FILE:T}
 
 step1:
 	@${.MAKE} -C ${TEST_DIR} -f step2.mk step2
@@ -52,9 +55,10 @@ step1:
 .elif ${.PARSEFILE:T} == "opt-m-step3.mk"
 
 # This file is included by step2.mk.
+.include <opt-m-check.mk>
 
 step2:
-	@echo ok
+	@echo ${CHECK}
 
 .else
 .  error
diff --git a/unit-tests/var-eval-short.exp b/unit-tests/var-eval-short.exp
index 14e3d372f198..6b42c27e22bc 100644
--- a/unit-tests/var-eval-short.exp
+++ b/unit-tests/var-eval-short.exp
@@ -1,5 +1,6 @@
-make: "var-eval-short.mk" line 46: In the :@ modifier of "", the variable name "${FAIL}" must not contain a dollar
+make: "var-eval-short.mk" line 46: while evaluating "${:Uword:@${FAIL}@expr@}": In the :@ modifier, the variable name "${FAIL}" must not contain a dollar
 make: "var-eval-short.mk" line 46: Malformed conditional (0 && ${:Uword:@${FAIL}@expr@})
+Parsing line 159: .if 0 && ${0:?${FAIL}then:${FAIL}else}
 CondParser_Eval: 0 && ${0:?${FAIL}then:${FAIL}else}
 Var_Parse: ${0:?${FAIL}then:${FAIL}else} (parse-only)
 Parsing modifier ${0:?...}
@@ -10,6 +11,7 @@ Modifier part: "${FAIL}else"
 Result of ${0:?${FAIL}then:${FAIL}else} is "" (parse-only, defined)
 Parsing line 167: DEFINED=	defined
 Global: DEFINED = defined
+Parsing line 168: .if 0 && ${DEFINED:L:?${FAIL}then:${FAIL}else}
 CondParser_Eval: 0 && ${DEFINED:L:?${FAIL}then:${FAIL}else}
 Var_Parse: ${DEFINED:L:?${FAIL}then:${FAIL}else} (parse-only)
 Parsing modifier ${DEFINED:L}
diff --git a/unit-tests/var-eval-short.mk b/unit-tests/var-eval-short.mk
index 2b25d82e96b8..5a42335a4474 100644
--- a/unit-tests/var-eval-short.mk
+++ b/unit-tests/var-eval-short.mk
@@ -1,4 +1,4 @@
-# $NetBSD: var-eval-short.mk,v 1.11 2023/10/19 18:24:33 rillig Exp $
+# $NetBSD: var-eval-short.mk,v 1.12 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for each variable modifier to ensure that they only do the minimum
 # necessary computations.  If the result of the expression is irrelevant,
@@ -41,7 +41,7 @@ FAIL=	${:!echo unexpected 1>&2!}
 # after the loop, when undefining the temporary global loop variable.
 # Since var.c 1.907 from 2021-04-04, a '$' is no longer allowed in the
 # variable name.
-# expect+2: In the :@ modifier of "", the variable name "${FAIL}" must not contain a dollar
+# expect+2: while evaluating "${:Uword:@${FAIL}@expr@}": In the :@ modifier, the variable name "${FAIL}" must not contain a dollar
 # expect+1: Malformed conditional (0 && ${:Uword:@${FAIL}@expr@})
 .if 0 && ${:Uword:@${FAIL}@expr@}
 .endif
diff --git a/unit-tests/var-op-expand.exp b/unit-tests/var-op-expand.exp
index 5ea4e6b6954c..0eafc9ae4c39 100644
--- a/unit-tests/var-op-expand.exp
+++ b/unit-tests/var-op-expand.exp
@@ -1,6 +1,6 @@
-make: "var-op-expand.mk" line 274: Unknown modifier "s,value,replaced,"
+make: "var-op-expand.mk" line 274: while evaluating variable "indirect": while evaluating variable "later": Unknown modifier "s,value,replaced,"
 make: "var-op-expand.mk" line 278: warning: XXX Neither branch should be taken.
-make: "var-op-expand.mk" line 283: Unknown modifier "s,value,replaced,"
+make: "var-op-expand.mk" line 283: while evaluating variable "indirect": while evaluating variable "later": Unknown modifier "s,value,replaced,"
 make: "var-op-expand.mk" line 285: warning: XXX Neither branch should be taken.
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/var-op-expand.mk b/unit-tests/var-op-expand.mk
index 76b90bf72b56..fb1e6d2c390f 100644
--- a/unit-tests/var-op-expand.mk
+++ b/unit-tests/var-op-expand.mk
@@ -1,4 +1,4 @@
-# $NetBSD: var-op-expand.mk,v 1.19 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: var-op-expand.mk,v 1.20 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the := variable assignment operator, which expands its
 # right-hand side.
@@ -270,7 +270,7 @@ later=	lowercase-value
 .undef later
 INDIRECT:=	${LATER:S,value,replaced,} OK ${LATER:value=sysv}
 indirect:=	${INDIRECT:tl}
-# expect+1: Unknown modifier "s,value,replaced,"
+# expect+1: while evaluating variable "indirect": while evaluating variable "later": Unknown modifier "s,value,replaced,"
 .if ${indirect} != " ok "
 .  error
 .else
@@ -279,7 +279,7 @@ indirect:=	${INDIRECT:tl}
 .endif
 LATER=	uppercase-value
 later=	lowercase-value
-# expect+1: Unknown modifier "s,value,replaced,"
+# expect+1: while evaluating variable "indirect": while evaluating variable "later": Unknown modifier "s,value,replaced,"
 .if ${indirect} != "uppercase-replaced ok uppercase-sysv"
 # expect+1: warning: XXX Neither branch should be taken.
 .  warning	XXX Neither branch should be taken.
diff --git a/unit-tests/vardebug.exp b/unit-tests/vardebug.exp
index a0aa6a301800..86f2ac0b420d 100644
--- a/unit-tests/vardebug.exp
+++ b/unit-tests/vardebug.exp
@@ -54,7 +54,7 @@ Var_Parse: ${:Uvariable:unknown} (eval-defined)
 Evaluating modifier ${:U...} on value "" (eval-defined, undefined)
 Result of ${:Uvariable} is "variable" (eval-defined, defined)
 Evaluating modifier ${:u...} on value "variable" (eval-defined, defined)
-make: "vardebug.mk" line 63: Unknown modifier "unknown"
+make: "vardebug.mk" line 63: while evaluating "${:Uvariable:unknown}": Unknown modifier "unknown"
 Result of ${:unknown} is error (eval-defined, defined)
 make: "vardebug.mk" line 63: Malformed conditional (${:Uvariable:unknown})
 Var_Parse: ${UNDEFINED} (eval-defined)
diff --git a/unit-tests/vardebug.mk b/unit-tests/vardebug.mk
index b9b094772b54..6c5703cb526f 100644
--- a/unit-tests/vardebug.mk
+++ b/unit-tests/vardebug.mk
@@ -1,4 +1,4 @@
-# $NetBSD: vardebug.mk,v 1.9 2023/12/20 09:46:00 rillig Exp $
+# $NetBSD: vardebug.mk,v 1.10 2024/04/20 10:18:55 rillig Exp $
 #
 # Demonstrates the debugging output for var.c.
 
@@ -59,7 +59,7 @@ VAR+=		3
 # as "is error", without surrounding quotes.
 # expect: Result of ${:unknown} is error (eval-defined, defined)
 # expect+2: Malformed conditional (${:Uvariable:unknown})
-# expect+1: Unknown modifier "unknown"
+# expect+1: while evaluating "${:Uvariable:unknown}": Unknown modifier "unknown"
 .if ${:Uvariable:unknown}
 .endif
 
diff --git a/unit-tests/varmisc.exp b/unit-tests/varmisc.exp
index 61e6a49963a0..dd24a419fe75 100644
--- a/unit-tests/varmisc.exp
+++ b/unit-tests/varmisc.exp
@@ -44,26 +44,26 @@ parse-dynamic: parse-dynamic parse-dynamic before
 parse-dynamic: parse-dynamic parse-dynamic after
 parse-dynamic: parse-dynamic parse-dynamic after
 varerror-unclosed:begin
-make: Unclosed variable ""
+make: in target "varerror-unclosed": Unclosed variable ""
 
-make: Unclosed variable "UNCLOSED"
+make: in target "varerror-unclosed": Unclosed variable "UNCLOSED"
 
-make: Unclosed variable "UNCLOSED"
+make: in target "varerror-unclosed": Unclosed variable "UNCLOSED"
 
-make: Unclosed variable "PATTERN"
+make: in target "varerror-unclosed": while evaluating variable "UNCLOSED": Unclosed variable "PATTERN"
 make: Unclosed expression, expecting '}' for modifier "M${PATTERN" of variable "UNCLOSED" with value ""
 
-make: Unclosed variable "param"
-make: Unclosed variable "UNCLOSED."
+make: in target "varerror-unclosed": Unclosed variable "param"
+make: in target "varerror-unclosed": Unclosed variable "UNCLOSED."
 
 
-make: Unclosed variable "UNCLOSED.1"
+make: in target "varerror-unclosed": Unclosed variable "UNCLOSED.1"
 
-make: Unclosed variable "UNCLOSED.2"
+make: in target "varerror-unclosed": Unclosed variable "UNCLOSED.2"
 
-make: Unclosed variable "UNCLOSED.3"
+make: in target "varerror-unclosed": Unclosed variable "UNCLOSED.3"
 
-make: Unclosed variable "UNCLOSED_ORIG"
+make: in target "varerror-unclosed": while evaluating variable "UNCLOSED_INDIR_2": while evaluating variable "UNCLOSED_INDIR_1": Unclosed variable "UNCLOSED_ORIG"
 
 varerror-unclosed:end
 target1-flags: we have: one two
diff --git a/unit-tests/varmod-assign.exp b/unit-tests/varmod-assign.exp
index f258f92ea05b..db1fa64c8479 100644
--- a/unit-tests/varmod-assign.exp
+++ b/unit-tests/varmod-assign.exp
@@ -42,7 +42,7 @@ mod-assign-empty: value}
 make: Bad modifier ":" for variable ""
 mod-assign-empty: overwritten}
 mod-assign-empty: VAR=overwritten
-make: Unknown modifier ":x"
+make: in target "mod-assign-parse": while evaluating variable "ASSIGN": Unknown modifier ":x"
 
 sysv:y
 make: Unfinished modifier for "ASSIGN" ('}' missing)
diff --git a/unit-tests/varmod-assign.mk b/unit-tests/varmod-assign.mk
index f7112c47c935..17d9df764be1 100644
--- a/unit-tests/varmod-assign.mk
+++ b/unit-tests/varmod-assign.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-assign.mk,v 1.19 2024/01/07 11:42:22 rillig Exp $
+# $NetBSD: varmod-assign.mk,v 1.20 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the obscure ::= variable modifiers, which perform variable
 # assignments during evaluation, just like the = operator in C.
@@ -90,7 +90,7 @@ mod-assign-empty:
 mod-assign-parse:
 	# The modifier for assignment operators starts with a ':'.
 	# An 'x' after that is an invalid modifier.
-	# expect: make: Unknown modifier ":x"
+	# expect: make: in target "mod-assign-parse": while evaluating variable "ASSIGN": Unknown modifier ":x"
 	@echo ${ASSIGN::x}
 
 	# When parsing an assignment operator fails because the operator is
diff --git a/unit-tests/varmod-edge.exp b/unit-tests/varmod-edge.exp
index c2477f16e950..fad5cb2c3c94 100644
--- a/unit-tests/varmod-edge.exp
+++ b/unit-tests/varmod-edge.exp
@@ -15,10 +15,10 @@ make: "varmod-edge.mk" line 184: ok eq-bs
 make: Unfinished modifier for "INP.eq-esc" ('=' missing)
 make: "varmod-edge.mk" line 184: ok eq-esc
 make: "varmod-edge.mk" line 184: ok colon
-make: "varmod-edge.mk" line 167: Unknown modifier ":"
-make: "varmod-edge.mk" line 167: Unknown modifier ":"
+make: "varmod-edge.mk" line 167: while evaluating variable "MOD.colons": while evaluating variable "INP.colons": Unknown modifier ":"
+make: "varmod-edge.mk" line 167: while evaluating variable "MOD.colons": while evaluating variable "INP.colons": Unknown modifier ":"
 make: "varmod-edge.mk" line 184: ok colons
-make: "varmod-edge.mk" line 195: Unknown modifier "Z"
+make: "varmod-edge.mk" line 195: while evaluating "${:Z}": Unknown modifier "Z"
 make: "varmod-edge.mk" line 195: Malformed conditional (${:Z})
 make: Unfinished modifier for "" (',' missing)
 make: "varmod-edge.mk" line 209: Malformed conditional (${:S,})
diff --git a/unit-tests/varmod-edge.mk b/unit-tests/varmod-edge.mk
index 91220d99e47d..2f8f8c793de1 100644
--- a/unit-tests/varmod-edge.mk
+++ b/unit-tests/varmod-edge.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-edge.mk,v 1.19 2023/11/19 22:06:15 rillig Exp $
+# $NetBSD: varmod-edge.mk,v 1.20 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for edge cases in variable modifiers.
 #
@@ -162,8 +162,8 @@ MOD.colons=	${INP.colons::::}
 EXP.colons=	# empty
 
 .for test in ${TESTS}
-# expect+2: Unknown modifier ":"
-# expect+1: Unknown modifier ":"
+# expect+2: while evaluating variable "MOD.colons": while evaluating variable "INP.colons": Unknown modifier ":"
+# expect+1: while evaluating variable "MOD.colons": while evaluating variable "INP.colons": Unknown modifier ":"
 .  if ${MOD.${test}} == ${EXP.${test}}
 # expect+16: ok M-paren
 # expect+15: ok M-mixed
@@ -191,7 +191,7 @@ EXP.colons=	# empty
 # XXX: The error message should mention the variable name of the expression,
 # even though that name is empty in this case.
 # expect+2: Malformed conditional (${:Z})
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating "${:Z}": Unknown modifier "Z"
 .if ${:Z}
 .  error
 .else
diff --git a/unit-tests/varmod-gmtime.exp b/unit-tests/varmod-gmtime.exp
index bbb8bd547bd5..1b12ead96d85 100644
--- a/unit-tests/varmod-gmtime.exp
+++ b/unit-tests/varmod-gmtime.exp
@@ -1,12 +1,12 @@
-make: "varmod-gmtime.mk" line 61: Invalid time value "-1"
+make: "varmod-gmtime.mk" line 61: while evaluating "${:L:gmtime=-1} != """: Invalid time value "-1"
 make: "varmod-gmtime.mk" line 61: Malformed conditional (${:L:gmtime=-1} != "")
-make: "varmod-gmtime.mk" line 72: Invalid time value " 1"
+make: "varmod-gmtime.mk" line 72: while evaluating "${:L:gmtime= 1} != """: Invalid time value " 1"
 make: "varmod-gmtime.mk" line 72: Malformed conditional (${:L:gmtime= 1} != "")
-make: "varmod-gmtime.mk" line 120: Invalid time value "10000000000000000000000000000000"
+make: "varmod-gmtime.mk" line 120: while evaluating "${:L:gmtime=10000000000000000000000000000000} != """: Invalid time value "10000000000000000000000000000000"
 make: "varmod-gmtime.mk" line 120: Malformed conditional (${:L:gmtime=10000000000000000000000000000000} != "")
-make: "varmod-gmtime.mk" line 133: Invalid time value "error"
+make: "varmod-gmtime.mk" line 133: while evaluating "${:L:gmtime=error} != """: Invalid time value "error"
 make: "varmod-gmtime.mk" line 133: Malformed conditional (${:L:gmtime=error} != "")
-make: "varmod-gmtime.mk" line 144: Invalid time value "100000S,1970,bad,"
+make: "varmod-gmtime.mk" line 144: while evaluating variable "%Y": Invalid time value "100000S,1970,bad,"
 make: "varmod-gmtime.mk" line 144: Malformed conditional (${%Y:L:gmtime=100000S,1970,bad,} != "bad")
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/varmod-gmtime.mk b/unit-tests/varmod-gmtime.mk
index c30f5edbecc2..db24b1680c46 100644
--- a/unit-tests/varmod-gmtime.mk
+++ b/unit-tests/varmod-gmtime.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-gmtime.mk,v 1.21 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: varmod-gmtime.mk,v 1.22 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the :gmtime variable modifier, which formats a timestamp
 # using strftime(3) in UTC.
@@ -56,7 +56,7 @@
 # 1970.  Going back 50 years in the past is not a practical use case for
 # make.  Therefore, since var.c 1.631, negative time stamps produce a
 # parse error.
-# expect+2: Invalid time value "-1"
+# expect+2: while evaluating "${:L:gmtime=-1} != """: Invalid time value "-1"
 # expect+1: Malformed conditional (${:L:gmtime=-1} != "")
 .if ${:L:gmtime=-1} != ""
 .  error
@@ -67,7 +67,7 @@
 
 # Spaces were allowed before var.c 1.631 from 2020-10-31 21:40:20, not
 # because it would make sense but just as a side-effect from using strtoul.
-# expect+2: Invalid time value " 1"
+# expect+2: while evaluating "${:L:gmtime= 1} != """: Invalid time value " 1"
 # expect+1: Malformed conditional (${:L:gmtime= 1} != "")
 .if ${:L:gmtime= 1} != ""
 .  error
@@ -115,7 +115,7 @@
 #
 # Since var.c 1.631 from 2020-10-31, the overflow is detected and produces a
 # parse error.
-# expect+2: Invalid time value "10000000000000000000000000000000"
+# expect+2: while evaluating "${:L:gmtime=10000000000000000000000000000000} != """: Invalid time value "10000000000000000000000000000000"
 # expect+1: Malformed conditional (${:L:gmtime=10000000000000000000000000000000} != "")
 .if ${:L:gmtime=10000000000000000000000000000000} != ""
 .  error
@@ -128,7 +128,7 @@
 # stopped after the '=', and the remaining string was parsed for more variable
 # modifiers.  Because of the unknown modifier 'e' from the 'error', the whole
 # variable value was discarded and thus not printed.
-# expect+2: Invalid time value "error"
+# expect+2: while evaluating "${:L:gmtime=error} != """: Invalid time value "error"
 # expect+1: Malformed conditional (${:L:gmtime=error} != "")
 .if ${:L:gmtime=error} != ""
 .  error
@@ -139,7 +139,7 @@
 # Before var.c 1.1050 from 2023-05-09, the timestamp could be directly
 # followed by the next modifier, without a ':' separator.  This was the same
 # bug as for the ':L' and ':P' modifiers.
-# expect+2: Invalid time value "100000S,1970,bad,"
+# expect+2: while evaluating variable "%Y": Invalid time value "100000S,1970,bad,"
 # expect+1: Malformed conditional (${%Y:L:gmtime=100000S,1970,bad,} != "bad")
 .if ${%Y:L:gmtime=100000S,1970,bad,} != "bad"
 .  error
diff --git a/unit-tests/varmod-hash.exp b/unit-tests/varmod-hash.exp
index 1286b456c6c2..e385c3b3ae11 100644
--- a/unit-tests/varmod-hash.exp
+++ b/unit-tests/varmod-hash.exp
@@ -1,9 +1,9 @@
-make: Unknown modifier "has"
+make: in target "all": while evaluating variable "12345": Unknown modifier "has"
 
 26bb0f5f
 12345
-make: Unknown modifier "hasX"
+make: in target "all": while evaluating variable "12345": Unknown modifier "hasX"
 
-make: Unknown modifier "hashed"
+make: in target "all": while evaluating variable "12345": Unknown modifier "hashed"
 
 exit status 0
diff --git a/unit-tests/varmod-ifelse.exp b/unit-tests/varmod-ifelse.exp
index 653fe104ddaa..8b9d41bd2427 100644
--- a/unit-tests/varmod-ifelse.exp
+++ b/unit-tests/varmod-ifelse.exp
@@ -16,7 +16,7 @@ CondParser_Eval: ${VAR} == value
 Comparing "value" == "value"
 Comparing "ok" != "ok"
 make: "varmod-ifelse.mk" line 158: no.
-make: "varmod-ifelse.mk" line 162: Comparison with '>=' requires both operands 'no' and '10' to be numeric
+make: "varmod-ifelse.mk" line 162: while evaluating variable "string == "literal" || no >= 10": Comparison with '>=' requires both operands 'no' and '10' to be numeric
 make: Bad conditional expression 'string == "literal" || no >= 10' before '?yes:no'
 make: "varmod-ifelse.mk" line 162: .
 make: Bad conditional expression 'string == "literal" &&  >= 10' before '?yes:no'
diff --git a/unit-tests/varmod-ifelse.mk b/unit-tests/varmod-ifelse.mk
index 5c8b55d92717..3bf433027950 100644
--- a/unit-tests/varmod-ifelse.mk
+++ b/unit-tests/varmod-ifelse.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-ifelse.mk,v 1.26 2023/12/10 20:12:28 rillig Exp $
+# $NetBSD: varmod-ifelse.mk,v 1.28 2024/04/23 22:51:28 rillig Exp $
 #
 # Tests for the ${cond:?then:else} variable modifier, which evaluates either
 # the then-expression or the else-expression, depending on the condition.
@@ -156,7 +156,7 @@ STRING=		string
 NUMBER=		no		# not really a number
 # expect+1: no.
 .info ${${STRING} == "literal" && ${NUMBER} >= 10:?yes:no}.
-# expect+3: Comparison with '>=' requires both operands 'no' and '10' to be numeric
+# expect+3: while evaluating variable "string == "literal" || no >= 10": Comparison with '>=' requires both operands 'no' and '10' to be numeric
 # expect: make: Bad conditional expression 'string == "literal" || no >= 10' before '?yes:no'
 # expect+1: .
 .info ${${STRING} == "literal" || ${NUMBER} >= 10:?yes:no}.
@@ -294,7 +294,7 @@ INDIRECT_COND2=	$${DELAYED} == "two"
 
 
 # In the modifier parts for the 'then' and 'else' branches, subexpressions are
-# parsed in by inspecting the actual modifiers.  In 2008, 2015, 2020, 2022 and
+# parsed by inspecting the actual modifiers.  In 2008, 2015, 2020, 2022 and
 # 2023, the exact parsing algorithm switched a few times, counting balanced
 # braces instead of proper subexpressions, which meant that unbalanced braces
 # were parsed differently, depending on whether the branch was active or not.
diff --git a/unit-tests/varmod-indirect.exp b/unit-tests/varmod-indirect.exp
index ecf52033ee4b..376beb8edef9 100644
--- a/unit-tests/varmod-indirect.exp
+++ b/unit-tests/varmod-indirect.exp
@@ -1,5 +1,5 @@
-make: "varmod-indirect.mk" line 19: Unknown modifier "${"
-make: "varmod-indirect.mk" line 52: Unknown modifier "${"
+make: "varmod-indirect.mk" line 19: while evaluating variable "value": Unknown modifier "${"
+make: "varmod-indirect.mk" line 52: while evaluating variable "value": Unknown modifier "${"
 make: "varmod-indirect.mk" line 54: warning: FIXME: this expression should have resulted in a parse error rather than returning the unparsed portion of the expression.
 make: "varmod-indirect.mk" line 143: before
 make: "varmod-indirect.mk" line 143: after
@@ -7,7 +7,7 @@ make: "varmod-indirect.mk" line 151: before
 make: "varmod-indirect.mk" line 151: after
 make: "varmod-indirect.mk" line 159: before
 make: "varmod-indirect.mk" line 159: after
-make: "varmod-indirect.mk" line 164: Unknown modifier "Z"
+make: "varmod-indirect.mk" line 164: while evaluating variable "UNDEF": Unknown modifier "Z"
 make: "varmod-indirect.mk" line 167: before
 make: "varmod-indirect.mk" line 167: after
 Parsing line 176: _:=	before ${UNDEF} after
@@ -31,7 +31,7 @@ Parsing line 195: _:=	before ${UNDEF:${:UZ}} after
 Var_Parse: ${UNDEF:${:UZ}} after (eval-keep-dollar-and-undefined)
 Indirect modifier "Z" from "${:UZ}"
 Evaluating modifier ${UNDEF:Z} on value "" (eval-keep-dollar-and-undefined, undefined)
-make: "varmod-indirect.mk" line 195: Unknown modifier "Z"
+make: "varmod-indirect.mk" line 195: while evaluating variable "UNDEF": Unknown modifier "Z"
 Result of ${UNDEF:Z} is error (eval-keep-dollar-and-undefined, undefined)
 Global: _ = before ${UNDEF:Z} after
 Parsing line 197: .MAKEFLAGS: -d0
diff --git a/unit-tests/varmod-indirect.mk b/unit-tests/varmod-indirect.mk
index 99e7215aa639..869231d47ebc 100644
--- a/unit-tests/varmod-indirect.mk
+++ b/unit-tests/varmod-indirect.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-indirect.mk,v 1.18 2024/02/04 10:03:10 rillig Exp $
+# $NetBSD: varmod-indirect.mk,v 1.19 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for indirect variable modifiers, such as in ${VAR:${M_modifiers}}.
 # These can be used for very basic purposes like converting a string to either
@@ -15,7 +15,7 @@
 # The following expression generates a parse error since its indirect
 # modifier contains more than a sole expression.
 #
-# expect+1: Unknown modifier "${"
+# expect+1: while evaluating variable "value": Unknown modifier "${"
 .if ${value:L:${:US}${:U,value,replacement,}} != "S,value,replacement,}"
 .  warning unexpected
 .endif
@@ -47,7 +47,7 @@
 # error.  Because of this parse error, this feature cannot be used reasonably
 # in practice.
 #
-# expect+2: Unknown modifier "${"
+# expect+2: while evaluating variable "value": Unknown modifier "${"
 #.MAKEFLAGS: -dvc
 .if ${value:L:${:UM*}S,value,replaced,} == "M*S,value,replaced,}"
 # expect+1: warning: FIXME: this expression should have resulted in a parse error rather than returning the unparsed portion of the expression.
@@ -160,7 +160,7 @@ M_NoPrimes=	${PRIMES:${M_ListToSkip}}
 .endfor
 
 # An error in an indirect modifier.
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating variable "UNDEF": Unknown modifier "Z"
 .for var in before ${UNDEF:${:UZ}} after
 # expect+2: before
 # expect+1: after
@@ -191,7 +191,7 @@ _:=	before ${UNDEF:${:U}} after
 # XXX: This expands to ${UNDEF:Z}, which will behave differently if the
 # variable '_' is used in a context where the expression ${_} is
 # parsed but not evaluated.
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating variable "UNDEF": Unknown modifier "Z"
 _:=	before ${UNDEF:${:UZ}} after
 
 .MAKEFLAGS: -d0
diff --git a/unit-tests/varmod-localtime.exp b/unit-tests/varmod-localtime.exp
index a7c3ff6ab932..1bb547289edd 100644
--- a/unit-tests/varmod-localtime.exp
+++ b/unit-tests/varmod-localtime.exp
@@ -1,12 +1,12 @@
-make: "varmod-localtime.mk" line 61: Invalid time value "-1"
+make: "varmod-localtime.mk" line 61: while evaluating "${:L:localtime=-1} != """: Invalid time value "-1"
 make: "varmod-localtime.mk" line 61: Malformed conditional (${:L:localtime=-1} != "")
-make: "varmod-localtime.mk" line 72: Invalid time value " 1"
+make: "varmod-localtime.mk" line 72: while evaluating "${:L:localtime= 1} != """: Invalid time value " 1"
 make: "varmod-localtime.mk" line 72: Malformed conditional (${:L:localtime= 1} != "")
-make: "varmod-localtime.mk" line 120: Invalid time value "10000000000000000000000000000000"
+make: "varmod-localtime.mk" line 120: while evaluating "${:L:localtime=10000000000000000000000000000000} != """: Invalid time value "10000000000000000000000000000000"
 make: "varmod-localtime.mk" line 120: Malformed conditional (${:L:localtime=10000000000000000000000000000000} != "")
-make: "varmod-localtime.mk" line 133: Invalid time value "error"
+make: "varmod-localtime.mk" line 133: while evaluating "${:L:localtime=error} != """: Invalid time value "error"
 make: "varmod-localtime.mk" line 133: Malformed conditional (${:L:localtime=error} != "")
-make: "varmod-localtime.mk" line 144: Invalid time value "100000S,1970,bad,"
+make: "varmod-localtime.mk" line 144: while evaluating variable "%Y": Invalid time value "100000S,1970,bad,"
 make: "varmod-localtime.mk" line 144: Malformed conditional (${%Y:L:localtime=100000S,1970,bad,} != "bad")
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/varmod-localtime.mk b/unit-tests/varmod-localtime.mk
index f6fcc61a7fa6..233e556e0c77 100644
--- a/unit-tests/varmod-localtime.mk
+++ b/unit-tests/varmod-localtime.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-localtime.mk,v 1.14 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: varmod-localtime.mk,v 1.15 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the :localtime variable modifier, which formats a timestamp
 # using strftime(3) in local time.
@@ -56,7 +56,7 @@
 # 1970.  Going back 50 years in the past is not a practical use case for
 # make.  Therefore, since var.c 1.631, negative time stamps produce a
 # parse error.
-# expect+2: Invalid time value "-1"
+# expect+2: while evaluating "${:L:localtime=-1} != """: Invalid time value "-1"
 # expect+1: Malformed conditional (${:L:localtime=-1} != "")
 .if ${:L:localtime=-1} != ""
 .  error
@@ -67,7 +67,7 @@
 
 # Spaces were allowed before var.c 1.631 from 2020-10-31 21:40:20, not
 # because it would make sense but just as a side-effect from using strtoul.
-# expect+2: Invalid time value " 1"
+# expect+2: while evaluating "${:L:localtime= 1} != """: Invalid time value " 1"
 # expect+1: Malformed conditional (${:L:localtime= 1} != "")
 .if ${:L:localtime= 1} != ""
 .  error
@@ -115,7 +115,7 @@
 #
 # Since var.c 1.631 from 2020-10-31, the overflow is detected and produces a
 # parse error.
-# expect+2: Invalid time value "10000000000000000000000000000000"
+# expect+2: while evaluating "${:L:localtime=10000000000000000000000000000000} != """: Invalid time value "10000000000000000000000000000000"
 # expect+1: Malformed conditional (${:L:localtime=10000000000000000000000000000000} != "")
 .if ${:L:localtime=10000000000000000000000000000000} != ""
 .  error
@@ -128,7 +128,7 @@
 # stopped after the '=', and the remaining string was parsed for more variable
 # modifiers.  Because of the unknown modifier 'e' from the 'error', the whole
 # variable value was discarded and thus not printed.
-# expect+2: Invalid time value "error"
+# expect+2: while evaluating "${:L:localtime=error} != """: Invalid time value "error"
 # expect+1: Malformed conditional (${:L:localtime=error} != "")
 .if ${:L:localtime=error} != ""
 .  error
@@ -139,7 +139,7 @@
 # Before var.c 1.1050 from 2023-05-09, the timestamp could be directly
 # followed by the next modifier, without a ':' separator.  This was the same
 # bug as for the ':L' and ':P' modifiers.
-# expect+2: Invalid time value "100000S,1970,bad,"
+# expect+2: while evaluating variable "%Y": Invalid time value "100000S,1970,bad,"
 # expect+1: Malformed conditional (${%Y:L:localtime=100000S,1970,bad,} != "bad")
 .if ${%Y:L:localtime=100000S,1970,bad,} != "bad"
 .  error
diff --git a/unit-tests/varmod-loop-delete.exp b/unit-tests/varmod-loop-delete.exp
index 47a2f74545a3..5c508a7a6420 100644
--- a/unit-tests/varmod-loop-delete.exp
+++ b/unit-tests/varmod-loop-delete.exp
@@ -1,4 +1,4 @@
-make: "varmod-loop-delete.mk" line 20: Cannot delete variable "VAR" while it is used
+make: "varmod-loop-delete.mk" line 20: while evaluating variable "VAR": while evaluating "${:U:@VAR@@} rest of the value": Cannot delete variable "VAR" while it is used
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
 exit status 1
diff --git a/unit-tests/varmod-loop-delete.mk b/unit-tests/varmod-loop-delete.mk
index 1ec6d361949d..cf0611991194 100644
--- a/unit-tests/varmod-loop-delete.mk
+++ b/unit-tests/varmod-loop-delete.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-loop-delete.mk,v 1.3 2023/06/01 20:56:35 rillig Exp $
+# $NetBSD: varmod-loop-delete.mk,v 1.4 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the variable modifier ':@', which as a side effect allows to
 # delete an arbitrary variable.
@@ -16,7 +16,7 @@ VAR=	${:U:@VAR@@} rest of the value
 
 # In an assignment, the scope is 'Global'.  Since the variable 'VAR' is
 # defined in the global scope, it deletes itself.
-# expect+1: Cannot delete variable "VAR" while it is used
+# expect+1: while evaluating variable "VAR": while evaluating "${:U:@VAR@@} rest of the value": Cannot delete variable "VAR" while it is used
 EVAL:=	${VAR}
 .if ${EVAL} != " rest of the value"
 .  error
diff --git a/unit-tests/varmod-loop-varname.exp b/unit-tests/varmod-loop-varname.exp
index 2060b51c31df..cefd82093e29 100644
--- a/unit-tests/varmod-loop-varname.exp
+++ b/unit-tests/varmod-loop-varname.exp
@@ -1,10 +1,10 @@
-make: "varmod-loop-varname.mk" line 18: In the :@ modifier of "", the variable name "${:Ubar:S,b,v,}" must not contain a dollar
+make: "varmod-loop-varname.mk" line 18: while evaluating "${:Uone two three:@${:Ubar:S,b,v,}@+${var}+@} != "+one+ +two+ +three+"": In the :@ modifier, the variable name "${:Ubar:S,b,v,}" must not contain a dollar
 make: "varmod-loop-varname.mk" line 18: Malformed conditional (${:Uone two three:@${:Ubar:S,b,v,}@+${var}+@} != "+one+ +two+ +three+")
-make: "varmod-loop-varname.mk" line 89: In the :@ modifier of "1 2 3", the variable name "v$" must not contain a dollar
+make: "varmod-loop-varname.mk" line 89: while evaluating variable "1 2 3": In the :@ modifier, the variable name "v$" must not contain a dollar
 make: "varmod-loop-varname.mk" line 89: Malformed conditional (${1 2 3:L:@v$@($v)@} != "(1) (2) (3)")
-make: "varmod-loop-varname.mk" line 96: In the :@ modifier of "1 2 3", the variable name "v$$" must not contain a dollar
+make: "varmod-loop-varname.mk" line 96: while evaluating variable "1 2 3": In the :@ modifier, the variable name "v$$" must not contain a dollar
 make: "varmod-loop-varname.mk" line 96: Malformed conditional (${1 2 3:L:@v$$@($v)@} != "() () ()")
-make: "varmod-loop-varname.mk" line 103: In the :@ modifier of "1 2 3", the variable name "v$$$" must not contain a dollar
+make: "varmod-loop-varname.mk" line 103: while evaluating variable "1 2 3": In the :@ modifier, the variable name "v$$$" must not contain a dollar
 make: "varmod-loop-varname.mk" line 103: Malformed conditional (${1 2 3:L:@v$$$@($v)@} != "() () ()")
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/varmod-loop-varname.mk b/unit-tests/varmod-loop-varname.mk
index 6f7436f277da..7abf8610911a 100644
--- a/unit-tests/varmod-loop-varname.mk
+++ b/unit-tests/varmod-loop-varname.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-loop-varname.mk,v 1.6 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: varmod-loop-varname.mk,v 1.7 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the first part of the variable modifier ':@var@...@', which
 # contains the variable name to use during the loop.
@@ -13,7 +13,7 @@
 # dynamically.  There was no practical use-case for this.
 # Since var.c 1.907 from 2021-04-04, a '$' is no longer allowed in the
 # variable name.
-# expect+2: In the :@ modifier of "", the variable name "${:Ubar:S,b,v,}" must not contain a dollar
+# expect+2: while evaluating "${:Uone two three:@${:Ubar:S,b,v,}@+${var}+@} != "+one+ +two+ +three+"": In the :@ modifier, the variable name "${:Ubar:S,b,v,}" must not contain a dollar
 # expect+1: Malformed conditional (${:Uone two three:@${:Ubar:S,b,v,}@+${var}+@} != "+one+ +two+ +three+")
 .if ${:Uone two three:@${:Ubar:S,b,v,}@+${var}+@} != "+one+ +two+ +three+"
 .  error
@@ -84,21 +84,21 @@ RES3=		3
 # There's no point in allowing a dollar sign in that position.
 # Since var.c 1.907 from 2021-04-04, a '$' is no longer allowed in the
 # variable name.
-# expect+2: In the :@ modifier of "1 2 3", the variable name "v$" must not contain a dollar
+# expect+2: while evaluating variable "1 2 3": In the :@ modifier, the variable name "v$" must not contain a dollar
 # expect+1: Malformed conditional (${1 2 3:L:@v$@($v)@} != "(1) (2) (3)")
 .if ${1 2 3:L:@v$@($v)@} != "(1) (2) (3)"
 .  error
 .else
 .  error
 .endif
-# expect+2: In the :@ modifier of "1 2 3", the variable name "v$$" must not contain a dollar
+# expect+2: while evaluating variable "1 2 3": In the :@ modifier, the variable name "v$$" must not contain a dollar
 # expect+1: Malformed conditional (${1 2 3:L:@v$$@($v)@} != "() () ()")
 .if ${1 2 3:L:@v$$@($v)@} != "() () ()"
 .  error
 .else
 .  error
 .endif
-# expect+2: In the :@ modifier of "1 2 3", the variable name "v$$$" must not contain a dollar
+# expect+2: while evaluating variable "1 2 3": In the :@ modifier, the variable name "v$$$" must not contain a dollar
 # expect+1: Malformed conditional (${1 2 3:L:@v$$$@($v)@} != "() () ()")
 .if ${1 2 3:L:@v$$$@($v)@} != "() () ()"
 .  error
diff --git a/unit-tests/varmod-loop.exp b/unit-tests/varmod-loop.exp
index 356946f63a9b..6aef3fe86857 100644
--- a/unit-tests/varmod-loop.exp
+++ b/unit-tests/varmod-loop.exp
@@ -1,7 +1,9 @@
 Parsing line 91: USE_8_DOLLARS=	${:U1:@var@${8_DOLLARS}@} ${8_DOLLARS} $$$$$$$$
+Parsing line 92: .if ${USE_8_DOLLARS} != "\$\$\$\$ \$\$\$\$ \$\$\$\$"
 CondParser_Eval: ${USE_8_DOLLARS} != "\$\$\$\$ \$\$\$\$ \$\$\$\$"
 Comparing "$$$$ $$$$ $$$$" != "$$$$ $$$$ $$$$"
 Parsing line 96: SUBST_CONTAINING_LOOP:= ${USE_8_DOLLARS}
+Parsing line 118: .if ${SUBST_CONTAINING_LOOP} != "\$\$ \$\$\$\$ \$\$\$\$"
 CondParser_Eval: ${SUBST_CONTAINING_LOOP} != "\$\$ \$\$\$\$ \$\$\$\$"
 Comparing "$$ $$$$ $$$$" != "$$ $$$$ $$$$"
 Parsing line 121: .MAKEFLAGS: -d0
diff --git a/unit-tests/varmod-match-escape.exp b/unit-tests/varmod-match-escape.exp
index 9a8f9ccf6082..d6bd804a7e89 100755
--- a/unit-tests/varmod-match-escape.exp
+++ b/unit-tests/varmod-match-escape.exp
@@ -33,9 +33,9 @@ Comparing ":" != "::"
 make: "varmod-match-escape.mk" line 43: warning: XXX: Oops
 Global: .MAKEFLAGS =  -r -k -d cv -d
 Global: .MAKEFLAGS =  -r -k -d cv -d 0
-make: "varmod-match-escape.mk" line 69: Dollar followed by nothing
-make: "varmod-match-escape.mk" line 110: warning: Unfinished character list in pattern '[A-]' of modifier ':M'
-make: "varmod-match-escape.mk" line 110: warning: Unfinished character list in pattern '[^A-]' of modifier ':M'
+make: "varmod-match-escape.mk" line 69: while evaluating "${:U\$:M\$} != """: Dollar followed by nothing
+make: "varmod-match-escape.mk" line 110: while evaluating variable "WORDS": warning: Unfinished character list in pattern '[A-]' of modifier ':M'
+make: "varmod-match-escape.mk" line 110: while evaluating variable "WORDS": warning: Unfinished character list in pattern '[^A-]' of modifier ':M'
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
 exit status 1
diff --git a/unit-tests/varmod-match-escape.mk b/unit-tests/varmod-match-escape.mk
index 1da3918fe1a5..d39ece1cba2c 100755
--- a/unit-tests/varmod-match-escape.mk
+++ b/unit-tests/varmod-match-escape.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-match-escape.mk,v 1.12 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: varmod-match-escape.mk,v 1.13 2024/04/20 10:18:55 rillig Exp $
 #
 # As of 2020-08-01, the :M and :N modifiers interpret backslashes differently,
 # depending on whether there was an expression somewhere before the
@@ -65,7 +65,7 @@ VALUES=		: :: :\:
 
 # In lint mode, the case of a lonely '$' is covered with an error message.
 .MAKEFLAGS: -dL
-# expect+1: Dollar followed by nothing
+# expect+1: while evaluating "${:U\$:M\$} != """: Dollar followed by nothing
 .if ${:U\$:M\$} != ""
 .  error
 .endif
@@ -105,8 +105,8 @@ EXP.[^A-]]=	a
 EXP.[^A-]]]=	a]
 
 .for pattern in [A-] [A-]] [A-]]] [^A-] [^A-]] [^A-]]]
-# expect+2: warning: Unfinished character list in pattern '[A-]' of modifier ':M'
-# expect+1: warning: Unfinished character list in pattern '[^A-]' of modifier ':M'
+# expect+2: while evaluating variable "WORDS": warning: Unfinished character list in pattern '[A-]' of modifier ':M'
+# expect+1: while evaluating variable "WORDS": warning: Unfinished character list in pattern '[^A-]' of modifier ':M'
 .  if ${WORDS:M${pattern}} != ${EXP.${pattern}}
 .    warning ${pattern}: ${WORDS:M${pattern}} != ${EXP.${pattern}}
 .  endif
diff --git a/unit-tests/varmod-match.exp b/unit-tests/varmod-match.exp
index e4e0783a7b15..3425eae2d421 100644
--- a/unit-tests/varmod-match.exp
+++ b/unit-tests/varmod-match.exp
@@ -1,14 +1,14 @@
-make: "varmod-match.mk" line 289: warning: Unfinished character list in pattern 'a[' of modifier ':M'
-make: "varmod-match.mk" line 297: warning: Unfinished character list in pattern 'a[^' of modifier ':M'
-make: "varmod-match.mk" line 305: warning: Unfinished character list in pattern '[-x1-3' of modifier ':M'
-make: "varmod-match.mk" line 313: warning: Unfinished character list in pattern '*[-x1-3' of modifier ':M'
-make: "varmod-match.mk" line 322: warning: Unfinished character list in pattern '[^-x1-3' of modifier ':M'
-make: "varmod-match.mk" line 336: warning: Unfinished character list in pattern '?[\' of modifier ':M'
-make: "varmod-match.mk" line 344: warning: Unfinished character range in pattern '[x-' of modifier ':M'
-make: "varmod-match.mk" line 356: warning: Unfinished character range in pattern '[^x-' of modifier ':M'
-make: "varmod-match.mk" line 364: warning: Unfinished character list in pattern '[' of modifier ':M'
-make: "varmod-match.mk" line 364: Unknown modifier "]"
-make: "varmod-match.mk" line 364: Malformed conditional (${ ${:U\:} ${:U\:\:} :L:M[:]} != ":")
+make: "varmod-match.mk" line 290: while evaluating variable "WORDS": warning: Unfinished character list in pattern 'a[' of modifier ':M'
+make: "varmod-match.mk" line 298: while evaluating variable "WORDS": warning: Unfinished character list in pattern 'a[^' of modifier ':M'
+make: "varmod-match.mk" line 306: while evaluating variable "WORDS": warning: Unfinished character list in pattern '[-x1-3' of modifier ':M'
+make: "varmod-match.mk" line 314: while evaluating variable "WORDS": warning: Unfinished character list in pattern '*[-x1-3' of modifier ':M'
+make: "varmod-match.mk" line 323: while evaluating variable "WORDS": warning: Unfinished character list in pattern '[^-x1-3' of modifier ':M'
+make: "varmod-match.mk" line 337: while evaluating variable "WORDS": warning: Unfinished character list in pattern '?[\' of modifier ':M'
+make: "varmod-match.mk" line 345: while evaluating variable "WORDS": warning: Unfinished character range in pattern '[x-' of modifier ':M'
+make: "varmod-match.mk" line 357: while evaluating variable "WORDS": warning: Unfinished character range in pattern '[^x-' of modifier ':M'
+make: "varmod-match.mk" line 365: while evaluating variable " : :: ": warning: Unfinished character list in pattern '[' of modifier ':M'
+make: "varmod-match.mk" line 365: while evaluating variable " : :: ": Unknown modifier "]"
+make: "varmod-match.mk" line 365: Malformed conditional (${ ${:U\:} ${:U\:\:} :L:M[:]} != ":")
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
 exit status 1
diff --git a/unit-tests/varmod-match.mk b/unit-tests/varmod-match.mk
index d93d1839192d..e91ddc7ce04b 100644
--- a/unit-tests/varmod-match.mk
+++ b/unit-tests/varmod-match.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-match.mk,v 1.20 2023/12/17 23:19:02 rillig Exp $
+# $NetBSD: varmod-match.mk,v 1.22 2024/04/23 22:51:28 rillig Exp $
 #
 # Tests for the ':M' modifier, which keeps only those words that match the
 # given pattern.
@@ -33,22 +33,22 @@
 # The pattern character '?' matches exactly 1 character, the pattern character
 # '*' matches 0 or more characters.  The whole pattern matches all words that
 # start with 's' and have 3 or more characters.
-.if ${One Two Three Four five six seven:L:Ms??*} != "six seven"
+.if ${One Two Three Four five six seven so s:L:Ms??*} != "six seven"
 .  error
 .endif
 
-# Ensure that a pattern without placeholders only matches itself.
+# A pattern without placeholders only matches itself.
 .if ${a aa aaa b ba baa bab:L:Ma} != "a"
 .  error
 .endif
 
-# Ensure that a pattern that ends with '*' is properly anchored at the
+# A pattern that ends with '*' is anchored at the
 # beginning.
 .if ${a aa aaa b ba baa bab:L:Ma*} != "a aa aaa"
 .  error
 .endif
 
-# Ensure that a pattern that starts with '*' is properly anchored at the end.
+# A pattern that starts with '*' is anchored at the end.
 .if ${a aa aaa b ba baa bab:L:M*a} != "a aa aaa ba baa"
 .  error
 .endif
@@ -257,8 +257,9 @@ ${:U*}=		asterisk
 .  error
 .endif
 
-# Without the modifier ':tW', the string is split into words.  All whitespace
-# around and between the words is normalized to a single space.
+# Without the modifier ':tW', the string is split into words.  Whitespace
+# around the words is discarded, and whitespace between the words is
+# normalized to a single space.
 .if ${   plain    string   :L:M*} != "plain string"
 .  error
 .endif
@@ -285,7 +286,7 @@ ${:U*}=		asterisk
 
 #	[	Incomplete empty character list, never matches.
 WORDS=		a a[
-# expect+1: warning: Unfinished character list in pattern 'a[' of modifier ':M'
+# expect+1: while evaluating variable "WORDS": warning: Unfinished character list in pattern 'a[' of modifier ':M'
 .if ${WORDS:Ma[} != ""
 .  error
 .endif
@@ -293,7 +294,7 @@ WORDS=		a a[
 #	[^	Incomplete negated empty character list, matches any single
 #		character.
 WORDS=		a a[ aX
-# expect+1: warning: Unfinished character list in pattern 'a[^' of modifier ':M'
+# expect+1: while evaluating variable "WORDS": warning: Unfinished character list in pattern 'a[^' of modifier ':M'
 .if ${WORDS:Ma[^} != "a[ aX"
 .  error
 .endif
@@ -301,7 +302,7 @@ WORDS=		a a[ aX
 #	[-x1-3	Incomplete character list, matches those elements that can be
 #		parsed without lookahead.
 WORDS=		- + x xx 0 1 2 3 4 [x1-3
-# expect+1: warning: Unfinished character list in pattern '[-x1-3' of modifier ':M'
+# expect+1: while evaluating variable "WORDS": warning: Unfinished character list in pattern '[-x1-3' of modifier ':M'
 .if ${WORDS:M[-x1-3} != "- x 1 2 3"
 .  error
 .endif
@@ -309,7 +310,7 @@ WORDS=		- + x xx 0 1 2 3 4 [x1-3
 #	*[-x1-3	Incomplete character list after a wildcard, matches those
 #		words that end with one of the characters from the list.
 WORDS=		- + x xx 0 1 2 3 4 00 01 10 11 000 001 010 011 100 101 110 111 [x1-3
-# expect+1: warning: Unfinished character list in pattern '*[-x1-3' of modifier ':M'
+# expect+1: while evaluating variable "WORDS": warning: Unfinished character list in pattern '*[-x1-3' of modifier ':M'
 .if ${WORDS:M*[-x1-3} != "- x xx 1 2 3 01 11 001 011 101 111 [x1-3"
 .  warning ${WORDS:M*[-x1-3}
 .endif
@@ -318,7 +319,7 @@ WORDS=		- + x xx 0 1 2 3 4 00 01 10 11 000 001 010 011 100 101 110 111 [x1-3
 #		Incomplete negated character list, matches any character
 #		except those elements that can be parsed without lookahead.
 WORDS=		- + x xx 0 1 2 3 4 [x1-3
-# expect+1: warning: Unfinished character list in pattern '[^-x1-3' of modifier ':M'
+# expect+1: while evaluating variable "WORDS": warning: Unfinished character list in pattern '[^-x1-3' of modifier ':M'
 .if ${WORDS:M[^-x1-3} != "+ 0 4"
 .  error
 .endif
@@ -332,7 +333,7 @@ WORDS=		- + x xx 0 1 2 3 4 [x1-3
 #		'\', as there is no following space that could be escaped.
 WORDS=		\\ \a ${:Ux\\}
 PATTERN=	${:U?[\\}
-# expect+1: warning: Unfinished character list in pattern '?[\' of modifier ':M'
+# expect+1: while evaluating variable "WORDS": warning: Unfinished character list in pattern '?[\' of modifier ':M'
 .if ${WORDS:M${PATTERN}} != "\\\\ x\\"
 .  error
 .endif
@@ -340,7 +341,7 @@ PATTERN=	${:U?[\\}
 #	[x-	Incomplete character list containing an incomplete character
 #		range, matches only the 'x'.
 WORDS=		[x- x x- y
-# expect+1: warning: Unfinished character range in pattern '[x-' of modifier ':M'
+# expect+1: while evaluating variable "WORDS": warning: Unfinished character range in pattern '[x-' of modifier ':M'
 .if ${WORDS:M[x-} != "x"
 .  error
 .endif
@@ -352,14 +353,14 @@ WORDS=		[x- x x- y
 #		XXX: Even matches strings that are longer than a single
 #		character.
 WORDS=		[x- x x- y yyyyy
-# expect+1: warning: Unfinished character range in pattern '[^x-' of modifier ':M'
+# expect+1: while evaluating variable "WORDS": warning: Unfinished character range in pattern '[^x-' of modifier ':M'
 .if ${WORDS:M[^x-} != "[x- y yyyyy"
 .  error
 .endif
 
 #	[:]	matches never since the ':' starts the next modifier
-# expect+3: warning: Unfinished character list in pattern '[' of modifier ':M'
-# expect+2: Unknown modifier "]"
+# expect+3: while evaluating variable " : :: ": warning: Unfinished character list in pattern '[' of modifier ':M'
+# expect+2: while evaluating variable " : :: ": Unknown modifier "]"
 # expect+1: Malformed conditional (${ ${:U\:} ${:U\:\:} :L:M[:]} != ":")
 .if ${ ${:U\:} ${:U\:\:} :L:M[:]} != ":"
 .  error
@@ -372,9 +373,16 @@ WORDS=		[x- x x- y yyyyy
 
 # Before var.c 1.1031 from 2022-08-24, the following expressions caused an
 # out-of-bounds read beyond the indirect ':M' modifiers.
-.if ${:U:${:UM\\}}		# The ':M' pattern need not be unescaped, the
-.  error			# resulting pattern is '\', it never matches
-.endif				# anything.
-.if ${:U:${:UM\\\:\\}}		# The ':M' pattern must be unescaped, the
-.  error			# resulting pattern is ':\', it never matches
-.endif				# anything.
+#
+# The argument to the inner ':U' is unescaped to 'M\'.
+# This 'M\' becomes an # indirect modifier ':M' with the pattern '\'.
+# The pattern '\' never matches.
+.if ${:U:${:UM\\}}
+.  error
+.endif
+# The argument to the inner ':U' is unescaped to 'M\:\'.
+# This 'M\:\' becomes an indirect modifier ':M' with the pattern ':\'.
+# The pattern ':\' never matches.
+.if ${:U:${:UM\\\:\\}}
+.  error
+.endif
diff --git a/unit-tests/varmod-mtime.exp b/unit-tests/varmod-mtime.exp
index 039173feddc3..87f405573437 100644
--- a/unit-tests/varmod-mtime.exp
+++ b/unit-tests/varmod-mtime.exp
@@ -1,13 +1,13 @@
-make: "varmod-mtime.mk" line 47: Invalid argument '123x' for modifier ':mtime'
+make: "varmod-mtime.mk" line 47: while evaluating variable "no/such/file": Invalid argument '123x' for modifier ':mtime'
 make: "varmod-mtime.mk" line 47: Malformed conditional (${no/such/file:L:mtime=123x})
-make: "varmod-mtime.mk" line 70: Cannot determine mtime for 'no/such/file1': <ENOENT>
-make: "varmod-mtime.mk" line 70: Cannot determine mtime for 'no/such/file2': <ENOENT>
+make: "varmod-mtime.mk" line 70: while evaluating variable "no/such/file1 no/such/file2": Cannot determine mtime for 'no/such/file1': <ENOENT>
+make: "varmod-mtime.mk" line 70: while evaluating variable "no/such/file1 no/such/file2": Cannot determine mtime for 'no/such/file2': <ENOENT>
 make: "varmod-mtime.mk" line 70: Malformed conditional (${no/such/file1 no/such/file2:L:mtime=error})
-make: "varmod-mtime.mk" line 81: Invalid argument 'errorhandler-no' for modifier ':mtime'
+make: "varmod-mtime.mk" line 81: while evaluating variable "MAKEFILE": Invalid argument 'errorhandler-no' for modifier ':mtime'
 make: "varmod-mtime.mk" line 81: Malformed conditional (${MAKEFILE:mtime=errorhandler-no} > 0)
-make: "varmod-mtime.mk" line 90: Invalid argument 'warn' for modifier ':mtime'
+make: "varmod-mtime.mk" line 90: while evaluating variable "MAKEFILE": Invalid argument 'warn' for modifier ':mtime'
 make: "varmod-mtime.mk" line 90: Malformed conditional (${MAKEFILE:mtime=warn} > 0)
-make: "varmod-mtime.mk" line 115: Unknown modifier "mtim"
+make: "varmod-mtime.mk" line 115: while evaluating variable "anything": Unknown modifier "mtim"
 make: "varmod-mtime.mk" line 115: Malformed conditional (${anything:L:mtim})
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/varmod-mtime.mk b/unit-tests/varmod-mtime.mk
index 298756e152c1..189bb8cadc9a 100644
--- a/unit-tests/varmod-mtime.mk
+++ b/unit-tests/varmod-mtime.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-mtime.mk,v 1.9 2023/12/17 14:07:22 rillig Exp $
+# $NetBSD: varmod-mtime.mk,v 1.10 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the ':mtime' variable modifier, which maps each word of the
 # expression to that file's modification time.
@@ -42,7 +42,7 @@ not_found_mtime:=	${no/such/file:L:mtime}
 
 
 # The fallback timestamp must only be an integer, without trailing characters.
-# expect+2: Invalid argument '123x' for modifier ':mtime'
+# expect+2: while evaluating variable "no/such/file": Invalid argument '123x' for modifier ':mtime'
 # expect+1: Malformed conditional (${no/such/file:L:mtime=123x})
 .if ${no/such/file:L:mtime=123x}
 .  error
@@ -64,8 +64,8 @@ _!=	rm -f ${COOKIE}
 # If the optional argument of the ':mtime' modifier is the word 'error', the
 # modifier fails with an error message, once for each affected file.
 #
-# expect+3: Cannot determine mtime for 'no/such/file1': <ENOENT>
-# expect+2: Cannot determine mtime for 'no/such/file2': <ENOENT>
+# expect+3: while evaluating variable "no/such/file1 no/such/file2": Cannot determine mtime for 'no/such/file1': <ENOENT>
+# expect+2: while evaluating variable "no/such/file1 no/such/file2": Cannot determine mtime for 'no/such/file2': <ENOENT>
 # expect+1: Malformed conditional (${no/such/file1 no/such/file2:L:mtime=error})
 .if ${no/such/file1 no/such/file2:L:mtime=error}
 .  error
@@ -76,7 +76,7 @@ _!=	rm -f ${COOKIE}
 
 # Only the word 'error' is a special argument to the ':mtime' modifier, all
 # other words result in a parse error.
-# expect+2: Invalid argument 'errorhandler-no' for modifier ':mtime'
+# expect+2: while evaluating variable "MAKEFILE": Invalid argument 'errorhandler-no' for modifier ':mtime'
 # expect+1: Malformed conditional (${MAKEFILE:mtime=errorhandler-no} > 0)
 .if ${MAKEFILE:mtime=errorhandler-no} > 0
 .else
@@ -85,7 +85,7 @@ _!=	rm -f ${COOKIE}
 
 
 # Only the word 'error' can be used as a fallback argument to the modifier.
-# expect+2: Invalid argument 'warn' for modifier ':mtime'
+# expect+2: while evaluating variable "MAKEFILE": Invalid argument 'warn' for modifier ':mtime'
 # expect+1: Malformed conditional (${MAKEFILE:mtime=warn} > 0)
 .if ${MAKEFILE:mtime=warn} > 0
 .  error
@@ -110,7 +110,7 @@ end:=	${%s:L:gmtime}
 
 
 # If there is a typo in the modifier name, it does not match.
-# expect+2: Unknown modifier "mtim"
+# expect+2: while evaluating variable "anything": Unknown modifier "mtim"
 # expect+1: Malformed conditional (${anything:L:mtim})
 .if ${anything:L:mtim}
 .  error
diff --git a/unit-tests/varmod-range.exp b/unit-tests/varmod-range.exp
index 9b0dad40a78e..d9848c2ef4f6 100644
--- a/unit-tests/varmod-range.exp
+++ b/unit-tests/varmod-range.exp
@@ -1,13 +1,13 @@
 make: "varmod-range.mk" line 43: Malformed conditional (${:range=5} != "")
-make: "varmod-range.mk" line 67: Invalid number "x}Rest" != "Rest"" for ':range' modifier
+make: "varmod-range.mk" line 67: while evaluating "${:U:range=x}Rest" != "Rest"": Invalid number "x}Rest" != "Rest"" for ':range' modifier
 make: "varmod-range.mk" line 67: Malformed conditional ("${:U:range=x}Rest" != "Rest")
-make: "varmod-range.mk" line 78: Unknown modifier "x0"
+make: "varmod-range.mk" line 78: while evaluating "${:U:range=0x0}Rest" != "Rest"": Unknown modifier "x0"
 make: "varmod-range.mk" line 78: Malformed conditional ("${:U:range=0x0}Rest" != "Rest")
-make: "varmod-range.mk" line 96: Unknown modifier "rang"
+make: "varmod-range.mk" line 96: while evaluating variable "a b c": Unknown modifier "rang"
 make: "varmod-range.mk" line 96: Malformed conditional ("${a b c:L:rang}Rest" != "Rest")
-make: "varmod-range.mk" line 105: Unknown modifier "rango"
+make: "varmod-range.mk" line 105: while evaluating variable "a b c": Unknown modifier "rango"
 make: "varmod-range.mk" line 105: Malformed conditional ("${a b c:L:rango}Rest" != "Rest")
-make: "varmod-range.mk" line 114: Unknown modifier "ranger"
+make: "varmod-range.mk" line 114: while evaluating variable "a b c": Unknown modifier "ranger"
 make: "varmod-range.mk" line 114: Malformed conditional ("${a b c:L:ranger}Rest" != "Rest")
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/varmod-range.mk b/unit-tests/varmod-range.mk
index 920001096054..2915100bfb79 100644
--- a/unit-tests/varmod-range.mk
+++ b/unit-tests/varmod-range.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-range.mk,v 1.10 2023/12/17 14:07:22 rillig Exp $
+# $NetBSD: varmod-range.mk,v 1.11 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the :range variable modifier, which generates sequences
 # of integers from the given range.
@@ -62,7 +62,7 @@
 #
 # Since 2020-11-01, the parser issues a more precise "Invalid number" error
 # instead.
-# expect+2: Invalid number "x}Rest" != "Rest"" for ':range' modifier
+# expect+2: while evaluating "${:U:range=x}Rest" != "Rest"": Invalid number "x}Rest" != "Rest"" for ':range' modifier
 # expect+1: Malformed conditional ("${:U:range=x}Rest" != "Rest")
 .if "${:U:range=x}Rest" != "Rest"
 .  error
@@ -73,7 +73,7 @@
 # The upper limit of the range must always be given in decimal.
 # This parse error stops at the 'x', trying to parse it as a variable
 # modifier.
-# expect+2: Unknown modifier "x0"
+# expect+2: while evaluating "${:U:range=0x0}Rest" != "Rest"": Unknown modifier "x0"
 # expect+1: Malformed conditional ("${:U:range=0x0}Rest" != "Rest")
 .if "${:U:range=0x0}Rest" != "Rest"
 .  error
@@ -91,7 +91,7 @@
 #.endif
 
 # modifier name too short
-# expect+2: Unknown modifier "rang"
+# expect+2: while evaluating variable "a b c": Unknown modifier "rang"
 # expect+1: Malformed conditional ("${a b c:L:rang}Rest" != "Rest")
 .if "${a b c:L:rang}Rest" != "Rest"
 .  error
@@ -100,7 +100,7 @@
 .endif
 
 # misspelled modifier name
-# expect+2: Unknown modifier "rango"
+# expect+2: while evaluating variable "a b c": Unknown modifier "rango"
 # expect+1: Malformed conditional ("${a b c:L:rango}Rest" != "Rest")
 .if "${a b c:L:rango}Rest" != "Rest"
 .  error
@@ -109,7 +109,7 @@
 .endif
 
 # modifier name too long
-# expect+2: Unknown modifier "ranger"
+# expect+2: while evaluating variable "a b c": Unknown modifier "ranger"
 # expect+1: Malformed conditional ("${a b c:L:ranger}Rest" != "Rest")
 .if "${a b c:L:ranger}Rest" != "Rest"
 .  error
diff --git a/unit-tests/varmod-subst-regex.exp b/unit-tests/varmod-subst-regex.exp
index a09046ef764c..25626ba18508 100644
--- a/unit-tests/varmod-subst-regex.exp
+++ b/unit-tests/varmod-subst-regex.exp
@@ -20,7 +20,7 @@ mod-regex-limits:22-ok:1 33 556
 mod-regex-limits:capture:ihgfedcbaabcdefghijABCDEFGHIJa0a1a2rest
 make: Regex compilation error: (details omitted)
 mod-regex-errors:
-make: Unknown modifier "Z"
+make: in target "mod-regex-errors": while evaluating variable "word": while evaluating "${:U:Z}y,W}": Unknown modifier "Z"
 mod-regex-errors: xy
 unmatched-subexpression.ok: one one 2 3 5 8 one3 2one 34
 make: No match for subexpression \2
diff --git a/unit-tests/varmod-subst.exp b/unit-tests/varmod-subst.exp
index 97fa2e4f1491..9d88b3d6fa6f 100644
--- a/unit-tests/varmod-subst.exp
+++ b/unit-tests/varmod-subst.exp
@@ -45,7 +45,7 @@ mod-subst-delimiter:
 1 two 3 tilde
 mod-subst-chain:
 A B c.
-make: Unknown modifier "i"
+make: in target "mod-subst-chain": while evaluating "${:Uvalue:S,a,x,i}.": Unknown modifier "i"
 .
 mod-subst-dollar:$1:
 mod-subst-dollar:$2:
diff --git a/unit-tests/varmod-to-separator.exp b/unit-tests/varmod-to-separator.exp
index a7d4ddb20147..6bdd6f0c2d43 100644
--- a/unit-tests/varmod-to-separator.exp
+++ b/unit-tests/varmod-to-separator.exp
@@ -1,6 +1,6 @@
-make: "varmod-to-separator.mk" line 155: Invalid character number at "400:tu}"
+make: "varmod-to-separator.mk" line 155: while evaluating variable "WORDS": Invalid character number at "400:tu}"
 make: "varmod-to-separator.mk" line 155: Malformed conditional (${WORDS:[1..3]:ts\400:tu})
-make: "varmod-to-separator.mk" line 171: Invalid character number at "100:tu}"
+make: "varmod-to-separator.mk" line 171: while evaluating variable "WORDS": Invalid character number at "100:tu}"
 make: "varmod-to-separator.mk" line 171: Malformed conditional (${WORDS:[1..3]:ts\x100:tu})
 make: Bad modifier ":ts\-300" for variable "WORDS"
 make: "varmod-to-separator.mk" line 179: Malformed conditional (${WORDS:[1..3]:ts\-300:tu})
@@ -18,7 +18,7 @@ make: Bad modifier ":t\X" for variable "WORDS"
 make: "varmod-to-separator.mk" line 232: Malformed conditional (${WORDS:t\X} != "anything")
 make: Bad modifier ":ts\69" for variable ""
 make: "varmod-to-separator.mk" line 249: Malformed conditional (${:Ua b:ts\69})
-make: "varmod-to-separator.mk" line 258: Invalid character number at "1F60E}"
+make: "varmod-to-separator.mk" line 258: while evaluating "${:Ua b:ts\x1F60E}": Invalid character number at "1F60E}"
 make: "varmod-to-separator.mk" line 258: Malformed conditional (${:Ua b:ts\x1F60E})
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/varmod-to-separator.mk b/unit-tests/varmod-to-separator.mk
index 57a7bd84ec44..8b8aeb4d3c33 100644
--- a/unit-tests/varmod-to-separator.mk
+++ b/unit-tests/varmod-to-separator.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-to-separator.mk,v 1.13 2023/11/19 21:47:52 rillig Exp $
+# $NetBSD: varmod-to-separator.mk,v 1.14 2024/04/20 10:18:55 rillig Exp $
 #
 # Tests for the :ts variable modifier, which joins the words of the variable
 # using an arbitrary character as word separator.
@@ -150,7 +150,7 @@ WORDS=	one two three four five six
 # for an unsigned character though.
 #
 # Since 2020-11-01, these out-of-bounds values are rejected.
-# expect+2: Invalid character number at "400:tu}"
+# expect+2: while evaluating variable "WORDS": Invalid character number at "400:tu}"
 # expect+1: Malformed conditional (${WORDS:[1..3]:ts\400:tu})
 .if ${WORDS:[1..3]:ts\400:tu}
 .  warning The separator \400 is accepted even though it is out of bounds.
@@ -166,7 +166,7 @@ WORDS=	one two three four five six
 # The hexadecimal number must be in the range of an unsigned char.
 #
 # Since 2020-11-01, these out-of-bounds values are rejected.
-# expect+2: Invalid character number at "100:tu}"
+# expect+2: while evaluating variable "WORDS": Invalid character number at "100:tu}"
 # expect+1: Malformed conditional (${WORDS:[1..3]:ts\x100:tu})
 .if ${WORDS:[1..3]:ts\x100:tu}
 .  warning The separator \x100 is accepted even though it is out of bounds.
@@ -253,7 +253,7 @@ WORDS=	one two three four five six
 .endif
 
 # Try whether bmake is Unicode-ready.
-# expect+2: Invalid character number at "1F60E}"
+# expect+2: while evaluating "${:Ua b:ts\x1F60E}": Invalid character number at "1F60E}"
 # expect+1: Malformed conditional (${:Ua b:ts\x1F60E})
 .if ${:Ua b:ts\x1F60E}		# U+1F60E "smiling face with sunglasses"
 .  error
diff --git a/unit-tests/varmod.exp b/unit-tests/varmod.exp
index 9ba0cb1d278b..22a7019dfc1a 100644
--- a/unit-tests/varmod.exp
+++ b/unit-tests/varmod.exp
@@ -1,7 +1,7 @@
 make: "varmod.mk" line 101: To escape a dollar, use \$, not $$, at "$$:L} != """
 make: "varmod.mk" line 101: Invalid variable name ':', at "$:L} != """
-make: "varmod.mk" line 107: Dollar followed by nothing
-make: "varmod.mk" line 117: Missing delimiter ':' after modifier "P"
+make: "varmod.mk" line 107: while evaluating "${:Uword:@word@${word}$@} != "word"": Dollar followed by nothing
+make: "varmod.mk" line 117: while evaluating variable "VAR": Missing delimiter ':' after modifier "P"
 make: "varmod.mk" line 119: Missing argument for ".error"
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/varmod.mk b/unit-tests/varmod.mk
index 45707ab9b886..c749dfb9659d 100644
--- a/unit-tests/varmod.mk
+++ b/unit-tests/varmod.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod.mk,v 1.10 2024/02/03 00:20:23 sjg Exp $
+# $NetBSD: varmod.mk,v 1.11 2024/04/20 10:18:56 rillig Exp $
 #
 # Tests for variable modifiers, such as :Q, :S,from,to or :Ufallback.
 #
@@ -103,7 +103,7 @@ DOLLAR2=	${:U\$}
 .endif
 
 # A '$' followed by nothing is an error as well.
-# expect+1: Dollar followed by nothing
+# expect+1: while evaluating "${:Uword:@word@${word}$@} != "word"": Dollar followed by nothing
 .if ${:Uword:@word@${word}$@} != "word"
 .  error
 .endif
@@ -113,7 +113,7 @@ DOLLAR2=	${:U\$}
 # XXX: The .error should not be reached since the expression is
 # malformed, and this error should be propagated up to Cond_EvalLine.
 VAR=	STOP
-# expect+1: Missing delimiter ':' after modifier "P"
+# expect+1: while evaluating variable "VAR": Missing delimiter ':' after modifier "P"
 .if ${VAR:P=RE} != "STORE"
 # expect+1: Missing argument for ".error"
 .  error
diff --git a/unit-tests/varname-dot-shell.exp b/unit-tests/varname-dot-shell.exp
index 22c2afe218a9..7d481fdf6ff1 100755
--- a/unit-tests/varname-dot-shell.exp
+++ b/unit-tests/varname-dot-shell.exp
@@ -6,6 +6,7 @@ Command: .SHELL = (details omitted)
 Global: ORIG_SHELL = (details omitted)
 Parsing line 12: .SHELL=		overwritten
 Global: ignoring '.SHELL = overwritten' due to a command line variable of the same name
+Parsing line 13: .if ${.SHELL} != ${ORIG_SHELL}
 CondParser_Eval: ${.SHELL} != ${ORIG_SHELL}
 Var_Parse: ${.SHELL} != ${ORIG_SHELL} (eval-defined)
 Var_Parse: ${ORIG_SHELL} (eval-defined)
@@ -13,6 +14,7 @@ Comparing "(details omitted)" != "(details omitted)"
 Parsing line 19: .MAKEFLAGS: .SHELL+=appended
 ParseDependency(.MAKEFLAGS: .SHELL+=appended)
 Command: ignoring '.SHELL += appended' as it is read-only
+Parsing line 20: .if ${.SHELL} != ${ORIG_SHELL}
 CondParser_Eval: ${.SHELL} != ${ORIG_SHELL}
 Var_Parse: ${.SHELL} != ${ORIG_SHELL} (eval-defined)
 Var_Parse: ${ORIG_SHELL} (eval-defined)
@@ -21,6 +23,7 @@ Parsing line 27: .undef .SHELL
 Global: ignoring delete '.SHELL' as it is not found
 Parsing line 28: .SHELL=		newly overwritten
 Global: ignoring '.SHELL = newly overwritten' due to a command line variable of the same name
+Parsing line 29: .if ${.SHELL} != ${ORIG_SHELL}
 CondParser_Eval: ${.SHELL} != ${ORIG_SHELL}
 Var_Parse: ${.SHELL} != ${ORIG_SHELL} (eval-defined)
 Var_Parse: ${ORIG_SHELL} (eval-defined)
diff --git a/unit-tests/varparse-errors.exp b/unit-tests/varparse-errors.exp
index 4193bea181c9..20fee23bddae 100644
--- a/unit-tests/varparse-errors.exp
+++ b/unit-tests/varparse-errors.exp
@@ -1,5 +1,5 @@
-make: "varparse-errors.mk" line 38: Unknown modifier "Z"
-make: "varparse-errors.mk" line 47: Unknown modifier "Z"
+make: "varparse-errors.mk" line 38: while evaluating "${:U:Z}": Unknown modifier "Z"
+make: "varparse-errors.mk" line 47: while evaluating "${:U:Z}post": Unknown modifier "Z"
 make: Bad modifier ":OX" for variable ""
 make: "varparse-errors.mk" line 71: Undefined variable "${:U:OX"
 make: Bad modifier ":OX" for variable ""
diff --git a/unit-tests/varparse-errors.mk b/unit-tests/varparse-errors.mk
index fc94d9dd3d18..edb02ef0b957 100644
--- a/unit-tests/varparse-errors.mk
+++ b/unit-tests/varparse-errors.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varparse-errors.mk,v 1.11 2023/11/19 22:32:44 rillig Exp $
+# $NetBSD: varparse-errors.mk,v 1.12 2024/04/20 10:18:56 rillig Exp $
 
 # Tests for parsing and evaluating all kinds of expressions.
 #
@@ -34,7 +34,7 @@ ERR_EVAL=	An evaluation error ${:Uvalue:C,.,\3,}.
 # As of 2020-12-01, errors in the variable name are silently ignored.
 # Since var.c 1.754 from 2020-12-20, unknown modifiers at parse time result
 # in an error message and a non-zero exit status.
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating "${:U:Z}": Unknown modifier "Z"
 VAR.${:U:Z}=	unknown modifier in the variable name
 .if ${VAR.} != "unknown modifier in the variable name"
 .  error
@@ -43,7 +43,7 @@ VAR.${:U:Z}=	unknown modifier in the variable name
 # As of 2020-12-01, errors in the variable name are silently ignored.
 # Since var.c 1.754 from 2020-12-20, unknown modifiers at parse time result
 # in an error message and a non-zero exit status.
-# expect+1: Unknown modifier "Z"
+# expect+1: while evaluating "${:U:Z}post": Unknown modifier "Z"
 VAR.${:U:Z}post=	unknown modifier with text in the variable name
 .if ${VAR.post} != "unknown modifier with text in the variable name"
 .  error