Merge sync of head

4 files changed, 45 insertions, 8 deletions

diff --git a/bin/expr/Makefile b/bin/expr/Makefile
index b86cf6686ab0..1d741b7e0b6d 100644
--- a/bin/expr/Makefile
+++ b/bin/expr/Makefile
@@ -1,9 +1,18 @@
 # $FreeBSD$
 
+.include <src.opts.mk>
+
 PROG=	expr
 SRCS=	expr.y
 YFLAGS=
 
+# expr relies on signed integer wrapping
+CFLAGS+= -fwrapv
+
 NO_WMISSING_VARIABLE_DECLARATIONS=
 
+.if ${MK_TESTS} != "no"
+SUBDIR+=	tests
+.endif
+
 .include <bsd.prog.mk>
diff --git a/bin/expr/expr.1 b/bin/expr/expr.1
index 34be0b8fa9de..d02105561fde 100644
--- a/bin/expr/expr.1
+++ b/bin/expr/expr.1
@@ -90,17 +90,17 @@ Return the evaluation of
 .Ar expr1
 if neither expression evaluates to an empty string or zero;
 otherwise, returns zero.
-.It Ar expr1 Li "{=, >, >=, <, <=, !=}" Ar expr2
+.It Ar expr1 Bro =, >, >=, <, <=, != Brc Ar expr2
 Return the results of integer comparison if both arguments are integers;
 otherwise, returns the results of string comparison using the locale-specific
 collation sequence.
 The result of each comparison is 1 if the specified relation is true,
 or 0 if the relation is false.
-.It Ar expr1 Li "{+, -}" Ar expr2
+.It Ar expr1 Bro +, - Brc Ar expr2
 Return the results of addition or subtraction of integer-valued arguments.
-.It Ar expr1 Li "{*, /, %}" Ar expr2
+.It Ar expr1 Bro *, /, % Brc Ar expr2
 Return the results of multiplication, integer division, or remainder of integer-valued arguments.
-.It Ar expr1 Li : Ar expr2
+.It Ar expr1 Li \&: Ar expr2
 The
 .Dq Li \&:
 operator matches
diff --git a/bin/expr/expr.y b/bin/expr/expr.y
index 1856ec84d0f7..0ddf3990d2a8 100644
--- a/bin/expr/expr.y
+++ b/bin/expr/expr.y
@@ -444,14 +444,26 @@ op_minus(struct val *a, struct val *b)
 	return (r);
 }
 
+/*
+ * We depend on undefined behaviour giving a result (in r).
+ * To test this result, pass it as volatile.  This prevents
+ * optimizing away of the test based on the undefined behaviour.
+ */
 void
-assert_times(intmax_t a, intmax_t b, intmax_t r)
+assert_times(intmax_t a, intmax_t b, volatile intmax_t r)
 {
 	/*
-	 * if first operand is 0, no overflow is possible,
-	 * else result of division test must match second operand
+	 * If the first operand is 0, no overflow is possible, 
+	 * else the result of the division test must match the
+	 * second operand.
+	 *
+	 * Be careful to avoid overflow in the overflow test, as
+	 * in assert_div().  Overflow in division would kill us
+	 * with a SIGFPE before getting the test wrong.  In old
+	 * buggy versions, optimization used to give a null test
+	 * instead of a SIGFPE.
 	 */
-	if (a != 0 && r / a != b)
+	if ((a == -1 && b == INTMAX_MIN) || (a != 0 && r / a != b))
 		errx(ERR_EXIT, "overflow");
 }
 
diff --git a/bin/expr/tests/Makefile b/bin/expr/tests/Makefile
new file mode 100644
index 000000000000..80c130c3df20
--- /dev/null
+++ b/bin/expr/tests/Makefile
@@ -0,0 +1,16 @@
+# $FreeBSD$
+
+OBJTOP=		${.OBJDIR}/../../..
+SRCTOP=		${.CURDIR}/../../..
+TESTSRC=	${SRCTOP}/contrib/netbsd-tests/bin/expr
+
+TESTSDIR=	${TESTSBASE}/bin/expr
+
+NETBSD_ATF_TESTS_SH=	expr_test
+
+ATF_TESTS_SH_SED_expr_test+=	-e 's/eval expr/eval expr --/g'
+ATF_TESTS_SH_SED_expr_test+=	-e 's/"expr: integer overflow or underflow occurred for operation.*"/"expr: overflow"/g'
+
+.include <netbsd-tests.test.mk>
+
+.include <bsd.test.mk>