[Bug lto/61602] New: ICE in lto1 on x86_64-linux-gnu in ipa_single_use, at ipa.c:1257

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61602

            Bug ID: 61602
           Summary: ICE in lto1 on x86_64-linux-gnu in ipa_single_use, at
                    ipa.c:1257
           Product: gcc
           Version: 4.10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu

The current gcc trunk produces an ICE at -O1 and above when compiling the
following code with LTO on x86_64-linux-gnu (in both 32-bit and 64-bit modes). 

This is a regression from 4.9.x. 


$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-unknown-linux-gnu/4.10.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-trunk/configure --prefix=/usr/local/gcc-trunk
--enable-languages=c,c++ --disable-werror --enable-multilib
Thread model: posix
gcc version 4.10.0 20140624 (experimental) [trunk revision 211926] (GCC) 
$ 
$ gcc-trunk -O1 small.c; a.out
$ gcc-4.9.0 -flto -O1 small.c; a.out
$ 
$ gcc-trunk -flto -O1 small.c
lto1: internal compiler error: in ipa_single_use, at ipa.c:1257
0x7581cb ipa_single_use
    ../../gcc-trunk/gcc/ipa.c:1257
0x7581cb execute
    ../../gcc-trunk/gcc/ipa.c:1305
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
lto-wrapper: fatal error: gcc-trunk returned 1 exit status
compilation terminated.
/usr/bin/ld: fatal error: lto-wrapper failed
collect2: error: ld returned 1 exit status
$ 


------------------------------------------


int a, *b[1] = { &a }, **c[1] = { &b[0] };

int
main ()
{
  b[0] = 0;
  return 0;
}