kbuild: strip whitespace in cmd_record_mcount findstring
CC_FLAGS_FTRACE may contain trailing whitespace that interferes with
findstring.
For example, commit 6977f95e63b9 ("powerpc: avoid -mno-sched-epilog on
GCC 4.9 and newer") introduced a change such that on my ppc64le box,
CC_FLAGS_FTRACE="-pg -mprofile-kernel ". (Note the trailing space.)
When cmd_record_mcount is now invoked, findstring fails as the ftrace
flags were found at very end of _c_flags, without the trailing space.
_c_flags=" ... -pg -mprofile-kernel"
CC_FLAGS_FTRACE="-pg -mprofile-kernel "
^
findstring is looking for this extra space
Remove the redundant whitespaces from CC_FLAGS_FTRACE in
cmd_record_mcount to avoid this problem.
[masahiro.yamada: This issue only happens in the released versions
of GNU Make. CC_FLAGS_FTRACE will not contain the trailing space if
you use the latest GNU Make, which contains commit b90fabc8d6f3
("* NEWS: Do not insert a space during '+=' if the value is empty.") ]
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com> (refactoring)
Fixes: 6977f95e63b9 ("powerpc: avoid -mno-sched-epilog on GCC 4.9 and newer").
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 2554a15..76ca30c 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -199,11 +199,8 @@
"$(if $(part-of-module),1,0)" "$(@)";
recordmcount_source := $(srctree)/scripts/recordmcount.pl
endif # BUILD_C_RECORDMCOUNT
-cmd_record_mcount = \
- if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" = \
- "$(CC_FLAGS_FTRACE)" ]; then \
- $(sub_cmd_record_mcount) \
- fi
+cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)), \
+ $(sub_cmd_record_mcount))
endif # CC_USING_RECORD_MCOUNT
endif # CONFIG_FTRACE_MCOUNT_RECORD