Re: [PATCH] tools/lib/api: undefine _FORTIFY_SOURCE before setting it

[Jiri Olsa <jolsa@redhat.com>]

On Sat, Apr 18, 2015 at 10:46:20AM -0400, Bobby Powers wrote:
> Some toolchains (like Hardened Gentoo) define _FORTIFY_SOURCE in the
> built-in, default args.  This causes perf builds to fail with:
> 
> <command-line>:0:0: error: "_FORTIFY_SOURCE" redefined [-Werror]
> <built-in>: note: this is the location of the previous definition
> cc1: all warnings being treated as errors
> 
> To avoid this, undefine _FORTIFY_SOURCE before (possibly
> re-)defining it in tools/lib/api.
> 
> Signed-off-by: Bobby Powers <bobbypowers@gmail.com>

Acked-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka

> ---
>  tools/lib/api/Makefile | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/lib/api/Makefile b/tools/lib/api/Makefile
> index 36c08b1..87c72d1 100644
> --- a/tools/lib/api/Makefile
> +++ b/tools/lib/api/Makefile
> @@ -21,7 +21,7 @@ LIB_OBJS += $(OUTPUT)fd/array.o
>  
>  LIBFILE = libapikfs.a
>  
> -CFLAGS = -ggdb3 -Wall -Wextra -std=gnu99 -Werror -O6 -D_FORTIFY_SOURCE=2 $(EXTRA_WARNINGS) $(EXTRA_CFLAGS) -fPIC
> +CFLAGS = -ggdb3 -Wall -Wextra -std=gnu99 -Werror -O6 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $(EXTRA_WARNINGS) $(EXTRA_CFLAGS) -fPIC
>  EXTLIBS = -lelf -lpthread -lrt -lm
>  ALL_CFLAGS = $(CFLAGS) $(BASIC_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
>  ALL_LDFLAGS = $(LDFLAGS)
> -- 
> 2.3.5
>