[Bug lto/51635] New: [4.7 regression] ICE in in dwarf2out_finish, at dwarf2out.c:22494 when building Firefox's libxul

["markus at trippelsdorf dot de" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51635

             Bug #: 51635
           Summary: [4.7 regression] ICE in in dwarf2out_finish, at
                    dwarf2out.c:22494 when building Firefox's libxul
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: markus@trippelsdorf.de


Created attachment 26152
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=26152
testcase patch

Firefox's libxul fails to build with -flto and -g:

lto1: internal compiler error: in dwarf2out_finish, at dwarf2out.c:22494

I've delta reduced the failure to two files and then reduced the
files individually.
Here's what I have thus far:

 % patch -p0 < patch
patching file Makefile
patching file test2.ii
patching file test.ii
 % make
gcc -r -nostdlib test2.ii test.ii -w -std=gnu++0x -pipe -g -Os -flto 
lto1: internal compiler error: in dwarf2out_finish, at dwarf2out.c:22494
Please submit a full bug report

Will keep trying to reduce the files further.