Re: [PATCH, rs6000, 4.9] Fix many powerpc*-linux ASAN test suite failures

[David Edelsohn <dje dot gcc at gmail dot com>]

This is okay with me if it is okay with the Release Managers.

Thanks, David

On Thu, Jul 17, 2014 at 10:56 AM, Peter Bergner <bergner@vnet.ibm.com> wrote:
> With a recent mainline libsanitizer merge from upstream, we're now seeing a
> lot of mainline ASAN test suite failures with the following error:
>
>  ==26426==ASan runtime does not come first in initial library list; you should
>  either link runtime to your application or manually preload it with LD_PRELOAD.
>  FAIL: c-c++-common/asan/asan-interface-1.c   -O0  execution test
>
> This is caused by mainline libasan detecting that libasan is not linked
> first and erroring out.  With the 4.8 and 4.9, we may just silently run
> into problems.  The root cause is that powerpc*-linux does not define
> LIBASAN_EARLY_SPEC which is defined in gnu-user.h.  It looks like all
> *-linux architectures include gnu-user.h except for powerpc*-linux.
> As discussed, for the 4.8 and 4.9 backports of the original patch, we
> will just copy those defines to the rs6000 header files and not try and
> include gnu-user.h itself.
>
> This is slightly different than the 4.8 patch, since the STATIC_LIB[AT]SAN_LIBS
> macro was deleted in 4.9.
>
> This passed bootstrap and regtesting on powerpc64-linux with no regressions.
> Ok for 4.9?
>
> Peter
>
>         * config/rs6000/sysv4.h:
>
> Index: gcc/config/rs6000/sysv4.h
> ===================================================================
> --- gcc/config/rs6000/sysv4.h   (revision 212695)
> +++ gcc/config/rs6000/sysv4.h   (working copy)
> @@ -949,3 +949,19 @@ ncrtn.o%s"
>  #define TARGET_USES_SYSV4_OPT 1
>
>  #undef DBX_REGISTER_NUMBER
> +
> +/* Link -lasan early on the command line.  For -static-libasan, don't link
> +   it for -shared link, the executable should be compiled with -static-libasan
> +   in that case, and for executable link link with --{,no-}whole-archive around
> +   it to force everything into the executable.  And similarly for -ltsan.  */
> +#if defined(HAVE_LD_STATIC_DYNAMIC)
> +#undef LIBASAN_EARLY_SPEC
> +#define LIBASAN_EARLY_SPEC "%{!shared:libasan_preinit%O%s} " \
> +  "%{static-libasan:%{!shared:" \
> +  LD_STATIC_OPTION " --whole-archive -lasan --no-whole-archive " \
> +  LD_DYNAMIC_OPTION "}}%{!static-libasan:-lasan}"
> +#undef LIBTSAN_EARLY_SPEC
> +#define LIBTSAN_EARLY_SPEC "%{static-libtsan:%{!shared:" \
> +  LD_STATIC_OPTION " --whole-archive -ltsan --no-whole-archive " \
> +  LD_DYNAMIC_OPTION "}}%{!static-libtsan:-ltsan}"
> +#endif
>
>