[Bug middle-end/68572] New: [4.9/5/6 Regression] ICE (segmentation fault)

[doko at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68572

            Bug ID: 68572
           Summary: [4.9/5/6 Regression] ICE (segmentation fault)
           Product: gcc
           Version: 5.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: doko at gcc dot gnu.org
  Target Milestone: ---

Created attachment 36852
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36852&action=edit
test case

seen with 4.9 branch, 5 branch and trunk on x86_64-linux-gnu, building with -O1
works around it.

$ /usr/lib/gcc-snapshot/bin/g++ -std=gnu++11 -fno-strict-aliasing -O2 -c
16_min.hM.min.ii 
16_min.hM.min.ii: In member function 'virtual void J::PopClip()':
16_min.hM.min.ii:77:1: error: statement uses released SSA name:
 }
 ^

# .MEM_31 = VDEF <.MEM>
MEM[(struct  &)_19] ={v} {CLOBBER};
The use of _19 should have been replaced
16_min.hM.min.ii:77:1: internal compiler error: cannot update SSA form
Please submit a full bug report,
with preprocessed source if appropriate.

I don't get a sensible backtrace from gdb.