[Bug tree-optimization/39203] LTO and -fwhole-program do not play along well

[dnovillo at google dot com]

------- Comment #3 from dnovillo at google dot com  2009-02-17 17:55 -------
Subject: Re:  LTO and -fwhole-program do not play 
        along well

On Tue, Feb 17, 2009 at 12:43, hubicka at ucw dot cz
<gcc-bugzilla@gcc.gnu.org> wrote:
>
>
> ------- Comment #2 from hubicka at ucw dot cz  2009-02-17 17:43 -------
> Subject: Re:  LTO and -fwhole-program do not play along well
>
> Hi,
> functions are brought local in function_and_variable_visibility that
> needs to be scheduled after LTO is read in.
> The pas computes externaly_visible flags that should be up-to-date for
> early IPA passes before LTO is written out, so I guess we need early
> function_and_vairable_visibility pass and late one where the first one
> is not bringing functions local at -fwhole-program -lto

OK, but I think there is a bigger issue here.  Even if -flto is *not*
used, we get link errors.  Just by compiling each file with
-fwhole-program is enough to reproduce the failure:

$ gcc -fwhole-program -c f1.c
$ gcc -fwhole-program -c f2.c
$ gcc -fwhole-program -o f f1.o f2.o

This is just a natural side-effect of using -fwhole-program.  It was
not intended to be used like this.


Diego.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39203