[Bug lto/45375] [meta-bug] Issues with building Mozilla with LTO

[markus at trippelsdorf dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45375

--- Comment #146 from Markus Trippelsdorf <markus at trippelsdorf dot de> 2012-12-02 07:36:02 UTC ---
(In reply to comment #145)
> > 
> > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45375
> > 
> > --- Comment #144 from Markus Trippelsdorf <markus at trippelsdorf dot de> 2012-12-01 12:39:30 UTC ---
> > It looks like there is a LTO code-size regression on trunk:
> > (size of libxul.so, build without elfhack):
> > 
> > gcc lto/pgo : size: 42204584 | Kraken bench: 2723.9ms +/- 0.9%
> 
> About LTO+PGO please be sure that you have the Teresa's fix from this Friday in
> your tree.

Yes, my tree already included this fix and also the fix from bug 55551.

> > gcc         : size: 34072808 | Kraken bench: 2804.3ms +/- 1.6%
> 
> Is LTO w/o PGO bigger than previous builds?

Couldn't tell, because it doesn't link:

/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/../../../../x86_64-pc-linux-gnu/bin/ld:
warning: hidden symbol 'pixman_add_triangles' in
/var/tmp/moz-build-dir/toolkit/library/../../gfx/cairo/libpixman/src/pixman-trap.o
is referenced by DSO /usr/lib64/libcairo.so
/usr/lib/gcc/x86_64-pc-linux-gnu/4.8.0/../../../../x86_64-pc-linux-gnu/bin/ld:
error: /tmp/cc0oq4BG.ltrans1.ltrans.o: requires dynamic R_X86_64_PC32 reloc
against '_ZN12SkAnnotationC1ER23SkFlattenableReadBuffer' which may overflow at
runtime; recompile with -fPIC
/tmp/cc0oq4BG.ltrans0.ltrans.o:cc0oq4BG.ltrans0.o:function SharedStub: error:
undefined reference to 'PrepareAndDispatch'
/tmp/cc0oq4BG.ltrans1.ltrans.o:cc0oq4BG.ltrans1.o:function
SkAnnotation::CreateProc(SkFlattenableReadBuffer&) [clone .local.7828.1055099]:
error: undefined reference to
'SkAnnotation::SkAnnotation(SkFlattenableReadBuffer&)'
collect2: error: ld returned 1 exit status

The undefined reference to PrepareAndDispatch is easily fixed by
an __attribute__ ((used)).
Do you have an idea on how to fix the
SkAnnotation::SkAnnotation(SkFlattenableReadBuffer&) issue?