[Bug target/68472] New: ICE: in ix86_get_modrm_for_rop, at config/i386/i386.c:27389 with -fPIC -mcmodel=medium -mmitigate-rop

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68472

            Bug ID: 68472
           Summary: ICE: in ix86_get_modrm_for_rop, at
                    config/i386/i386.c:27389 with -fPIC -mcmodel=medium
                    -mmitigate-rop
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz
  Target Milestone: ---

Created attachment 36798
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36798&action=edit
reduced testcase

Compiler output:
$ gcc -fPIC -mcmodel=medium -mmitigate-rop testcase.c
testcase.c: In function 'foo':
testcase.c:4:1: internal compiler error: in ix86_get_modrm_for_rop, at
config/i386/i386.c:27389
 }
 ^

0xe9ae60 ix86_get_modrm_for_rop
        /mnt/svn/gcc-trunk/gcc/config/i386/i386.c:27389
0xebb8bd ix86_mitigate_rop
        /mnt/svn/gcc-trunk/gcc/config/i386/i386.c:45266
0xebb8bd ix86_reorg
        /mnt/svn/gcc-trunk/gcc/config/i386/i386.c:45424
0xb01709 execute
        /mnt/svn/gcc-trunk/gcc/reorg.c:3945
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.


$ gcc -v                                             
Using built-in specs.
COLLECT_GCC=/mnt/svn/gcc-trunk/binary-latest/bin/gcc
COLLECT_LTO_WRAPPER=/mnt/svn/gcc-trunk/binary-230703-lto-fortran-checking-yes-rtl-df/bin/../libexec/gcc/x86_64-pc-linux-gnu/6.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /mnt/svn/gcc-trunk//configure --enable-checking=yes,rtl,df
--enable-languages=c,c++,lto,fortran
--prefix=/mnt/svn/gcc-trunk//binary-230703-lto-fortran-checking-yes-rtl-df/
--without-cloog --without-ppl --without-isl
Thread model: posix
gcc version 6.0.0 20151121 (experimental) (GCC) 


Tested revisions:
r230703 - ICE