perf tools: check if -DFORTIFY_SOURCE=2 is allowed

It seems gcc (4.7.2) defines _FORTIFY_SOURCE internally and becomes confused when it sees another definition in flags. For me, build failed like this: CHK glibc Makefile:548: *** No gnu/libc-version.h found, please install glibc-dev[el]/glibc-static. Stop. and only with V=1 it printed: <command-line>:0:0: error: "_FORTIFY_SOURCE" redefined [-Werror] <stdin>:1:0: note: this is the location of the previous definition Signed-off-by: Marcin Slusarz <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
vbatts · Mar 13, 2013 · d2f3247 · d2f3247
1 parent 5f7439e
commit d2f3247
Showing 1 changed file with 7 additions and 1 deletion.
diff --git a/tools/perf/Makefile b/tools/perf/Makefile
@@ -95,7 +95,7 @@ ifeq ("$(origin DEBUG)", "command line")
   PERF_DEBUG = $(DEBUG)
 endif
 ifndef PERF_DEBUG
-  CFLAGS_OPTIMIZE = -O6 -D_FORTIFY_SOURCE=2
+  CFLAGS_OPTIMIZE = -O6
 endif
 
 ifdef PARSER_DEBUG
@@ -180,6 +180,12 @@ ifeq ($(call try-cc,$(SOURCE_HELLO),$(CFLAGS) -Werror -Wvolatile-register-var,-W
        CFLAGS := $(CFLAGS) -Wvolatile-register-var
 endif
 
+ifndef PERF_DEBUG
+	ifeq ($(call try-cc,$(SOURCE_HELLO),$(CFLAGS) -D_FORTIFY_SOURCE=2,-D_FORTIFY_SOURCE=2),y)
+		CFLAGS := $(CFLAGS) -D_FORTIFY_SOURCE=2
+	endif
+endif
+
 ### --- END CONFIGURATION SECTION ---
 
 ifeq ($(srctree),)