[PATCH][Revised] Enable libsanitizer on darwin

[Alexander Potapenko]

Hi Jack,

most certainly the functionality of asan is not intact.
The error messages denote that mach_override couldn't parse some of
the function prologues, which means some of ASan interceptors just
won't work.
In order to fix this you need to change the DEBUG definition in
mach_override.c, look at the bytes being parsed and fix the
instruction table in mach_override.c
Please also send a patch to LLVM containing the fix (sending the patch
to the original mach_override repo makes little sense, because we've
forked it long time ago).

HTH,
Alex

On Wed, Nov 14, 2012 at 6:43 PM, Jack Howarth <howarth@bromo.med.uc.edu> wrote:
>    The attached patch assumes that mach_override/mach_override.h
> and mach_override/mach_override.c has been imported by the libsanitizer
> maintainers for use by darwin. The patch adds darwin to the supported
> target list in configure.tgt and defines USING_MACH_OVERRIDE for darwin
> in configure.ac. The definition of USING_MACH_OVERRIDE is used in
> Makefile.am as the test for appending mach_override/mach_override.c
> to libinterception_la_SOURCES. Tested on x86_64-apple-darwin12 against
> the mach_override/mach_override.h and mach_override/mach_override.c
> from llvm compiler-rt 3.2 branch. While there is some noise on the
> output of asan...
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55289#c14
>
> the functionality of asan appears to be intact. Okay for gcc trunk
> after the libsanitizer maintainers import the missing mach_override/mach_override.h
> and mach_override/mach_override.c files?
>               Jack
> ps Note that this patch assumes that both mach_override.h and mach_override.c
> reside in a mach_override subdirectory in interception as is the case in the
> llvm's compiler-rt.
> pps Patch to configure.tgt revised to use a distinct instance for darwin in
> the case statement and to limit libsanitizer to i?86 and x86_64 on darwin.
>
> libsanitizer/
>
> 2012-11-14  Jack Howarth <howarth@bromo.med.uc.edu>
>
>         * configure.tgt: Add darwin to supported targets.
>         * configure.ac: Define USING_MACH_OVERRIDE when on darwin.
>         * interception/Makefile.am: Compile mach_override.c when
>         USING_MACH_OVERRIDE defined.
>         * configure: Regenerated.
>         * interception/Makefile.in: Likewise.
>
> Index: libsanitizer/interception/Makefile.am
> ===================================================================
> --- libsanitizer/interception/Makefile.am       (revision 193500)
> +++ libsanitizer/interception/Makefile.am       (working copy)
> @@ -11,7 +11,11 @@ interception_files = \
>          interception_mac.cc \
>          interception_win.cc
>
> -libinterception_la_SOURCES = $(interception_files)
> +if USING_MACH_OVERRIDE
> +libinterception_la_SOURCES = $(interception_files) mach_override/mach_override.c
> +else
> +libinterception_la_SOURCES = $(interception_files)
> +endif
>
>  # Work around what appears to be a GNU make bug handling MAKEFLAGS
>  # values defined in terms of make variables, as is the case for CC and
> Index: libsanitizer/configure.ac
> ===================================================================
> --- libsanitizer/configure.ac   (revision 193500)
> +++ libsanitizer/configure.ac   (working copy)
> @@ -17,6 +17,12 @@ AM_PROG_LIBTOOL
>  AC_SUBST(enable_shared)
>  AC_SUBST(enable_static)
>
> +case "$host" in
> +  *-*-darwin*) MACH_OVERRIDE=true ;;
> +  *) MACH_OVERRIDE=false ;;
> +esac
> +AM_CONDITIONAL(USING_MACH_OVERRIDE, $MACH_OVERRIDE)
> +
>  #AM_ENABLE_MULTILIB(, ..)
>  target_alias=${target_alias-$host_alias}
>  AC_SUBST(target_alias)
> Index: libsanitizer/configure.tgt
> ===================================================================
> --- libsanitizer/configure.tgt  (revision 193500)
> +++ libsanitizer/configure.tgt  (working copy)
> @@ -22,6 +22,8 @@
>  case "${target}" in
>    x86_64-*-linux* | i?86-*-linux*)
>         ;;
> +  x86_64-*-darwin* | i?86-*-darwin*)
> +       ;;
>    *)
>         UNSUPPORTED=1
>         ;;



-- 
Alexander Potapenko
Software Engineer
Google Moscow