Commit-ID: c2bb9e32e2315971a8535fee77335c04a739d71d Gitweb: http://git.kernel.org/tip/c2bb9e32e2315971a8535fee77335c04a739d71d Author: Steven Rostedt <[email protected]> AuthorDate: Wed, 20 Apr 2016 11:32:35 -0400 Committer: Ingo Molnar <[email protected]> CommitDate: Fri, 22 Apr 2016 09:00:57 +0200
objtool: Fix Makefile to properly see if libelf is supported When doing a make allmodconfig, I hit the following compile error: In file included from builtin-check.c:32:0: elf.h:22:18: fatal error: gelf.h: No such file or directory compilation terminated. ... Digging into it, it appears that the $(shell ..) command in the Makefile does not give the proper result when it fails to find -lelf, and continues to compile objtool. Instead, use the "try-run" makefile macro to perform the test. This gives a proper result for both cases. Signed-off-by: Steven Rostedt <[email protected]> Acked-by: Josh Poimboeuf <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Bernd Petrovitsch <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Chris J Arges <[email protected]> Cc: Jiri Slaby <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Michal Marek <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Pedro Alves <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Fixes: 442f04c34a1a4 ("objtool: Add tool to perform compile-time stack metadata validation") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- Makefile | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 1d0aef0..70ca38e 100644 --- a/Makefile +++ b/Makefile @@ -1008,7 +1008,8 @@ prepare0: archprepare FORCE prepare: prepare0 prepare-objtool ifdef CONFIG_STACK_VALIDATION - has_libelf := $(shell echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf - &> /dev/null && echo 1 || echo 0) + has_libelf := $(call try-run,\ + echo "int main() {}" | $(HOSTCC) -xc -o /dev/null -lelf -,1,0) ifeq ($(has_libelf),1) objtool_target := tools/objtool FORCE else

