[PATCH] Fix --with-build-config=bootstrap-ubsan bootstrap of lto-plugin (PR sanitizer/56781)

[H.J. Lu]

On Tue, Mar 25, 2014 at 12:28 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> Hi!
>
> lto-plugin is another problematic directory in asan/ubsan bootstraps.
>
> Unlike fixincludes, it is bootstrapped, and like fixincludes it is also
> linked against host libiberty.  The problem for lto-plugin is that the
> -static-libubsan -fsanitize=undefined -B/some/path/to/libsanitizer/ -B/some/path/to/libsanitizer/ubsan/.libs/
> switches are eaten by libtool, which throws them away on the floor.
>
> We apparently have libtool-ldflags which is used by other libraries
> to filter some options so that libtool doesn't eat them, but even after
> applying the lto-plugin/Makefile.am changes I got failures, because
> while -fsanitize=undefined now made it through, the rest of the options
> didn't.  So, this patch also tweaks libtool-ldflags to handle some more
> options.
>

lto-plugin is dlopened by ld.  How does asan work in lto-plugin
when ld isn't compiled with asan?

-- 
H.J.