[Bug tree-optimization/58326] New: ICE in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:551

[su at cs dot ucdavis.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58326

            Bug ID: 58326
           Summary: ICE in check_loop_closed_ssa_use, at
                    tree-ssa-loop-manip.c:551
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu

The following code causes an ICE when compiled with the current gcc trunk at
-O2 and -O3 on x86_64-linux (both 32-bit and 64-bit modes). 

This is a regression from 4.8.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/4.9.0/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: ../gcc-trunk/configure
--enable-languages=c,c++,objc,obj-c++,fortran,lto
--with-gmp=/usr/local/gcc-trunk --with-mpfr=/usr/local/gcc-trunk
--with-mpc=/usr/local/gcc-trunk --with-cloog=/usr/local/gcc-trunk
--prefix=/usr/local/gcc-trunk
Thread model: posix
gcc version 4.9.0 20130905 (experimental) [trunk revision 202269] (GCC) 
$ gcc-trunk -O1 -c small.c
$ gcc-4.8 -O2 -c small.c  
$ gcc-trunk -O2 -c small.c
small.c: In function ‘foo’:
small.c:5:6: internal compiler error: in check_loop_closed_ssa_use, at
tree-ssa-loop-manip.c:551
 void foo ()
      ^
0xa25746 check_loop_closed_ssa_use
    ../../gcc-trunk/gcc/tree-ssa-loop-manip.c:550
0xa2717c check_loop_closed_ssa_stmt
    ../../gcc-trunk/gcc/tree-ssa-loop-manip.c:566
0xa2717c verify_loop_closed_ssa(bool)
    ../../gcc-trunk/gcc/tree-ssa-loop-manip.c:600
0xdc61d8 tree_unroll_loops_completely(bool, bool)
    ../../gcc-trunk/gcc/tree-ssa-loop-ivcanon.c:1239
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.
$ 


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


int a, *d; 
long b;
short c;

void foo ()
{
  int e;
 lbl:
  for (c = 0; c < 2; c++)
    {
      if (1 >> b)
    break;
      e = *d;
      for (; a; a++)
        {
      *d = e;
      if (b)
        goto lbl;
        }
    }
}