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Diffstat (limited to 'unit-tests/depsrc-ignore.mk')
| -rw-r--r-- | unit-tests/depsrc-ignore.mk | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/unit-tests/depsrc-ignore.mk b/unit-tests/depsrc-ignore.mk new file mode 100644 index 000000000000..1be3eabe8806 --- /dev/null +++ b/unit-tests/depsrc-ignore.mk @@ -0,0 +1,67 @@ +# $NetBSD: depsrc-ignore.mk,v 1.4 2020/08/29 16:13:27 rillig Exp $ +# +# Tests for the special source .IGNORE in dependency declarations, +# which ignores any command failures for that target. +# +# Even though ignore-errors fails, the all target is still made. +# Since the all target is not marked with .IGNORE, it stops at the +# first failing command. +# +# XXX: The ordering of the messages in the output is confusing. +# The "ignored" comes much too late to be related to the "false +# ignore-errors". This is due to stdout being buffered. +# +# The "continuing" message comes from the -k option. If there had been +# other targets independent of "all", these would be built as well. +# +# Enabling the debugging option -de changes the order in which the messages +# appear. Now the "ignored" message is issued in the correct position. +# The explanation for the output reordering is that the output is buffered. +# As the manual page says, in debugging mode stdout is line buffered. +# In these tests the output is redirected to a file, therefore stdout is +# fully buffered. +# +# This is what actually happens, as of 2020-08-29. To verify it, set the +# following breakpoints in CompatRunCommand: +# +# * the "!silent" line, to see all commands. +# * the "fflush" line, to see stdout being flushed. +# * the "status = WEXITSTATUS" line +# * the "(continuing)" line +# * the "(ignored)" line +# +# The breakpoints are visited in the following order: +# +# "ignore-errors begin" +# Goes directly to STDOUT_FILENO since it is run in a child process. +# "false ignore-errors" +# Goes to the stdout buffer (CompatRunCommand, keyword "!silent") and +# the immediate call to fflush(stdout) copies it to STDOUT_FILENO. +# "*** Error code 1 (ignored)" +# Goes to the stdout buffer but is not flushed (CompatRunCommand, near +# the end). +# "ignore-errors end" +# Goes directly to STDOUT_FILENO. +# "all begin" +# Goes directly to STDOUT_FILENO. +# "false all" +# Goes to the stdout buffer, where the "*** Error code 1 (ignored)" is +# still waiting to be flushed. These two lines are flushed now. +# "*** Error code 1 (continuing)" +# Goes to the stdout buffer. +# "Stop." +# Goes to the stdout buffer. +# exit(1) +# Flushes the stdout buffer to STDOUT_FILENO. + +all: ignore-errors + +ignore-errors: .IGNORE + @echo $@ begin + false $@ + @echo $@ end + +all: + @echo $@ begin + false $@ + @echo $@ end |