[Bug middle-end/67821] New: [gcc 5 regression] ICE in duplicate_ssa_name_range_info

[s...@li-snyder.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67821

            Bug ID: 67821
           Summary: [gcc 5 regression] ICE in
                    duplicate_ssa_name_range_info
           Product: gcc
           Version: 5.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: s...@li-snyder.org
  Target Milestone: ---

Created attachment 36438
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36438&action=edit
test case

hi -

I'm testing gcc from the gcc-5-branch svn branch.
Using the version as of 2 oct 2015 (svn rev 228385), i get an ICE compiling
the attached if -O2 is used.  (Reduced from core/clib/src/Demangle.c
in root 6.02.08, which appears itself to have been copied from libiberty.)

$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/local/gcc/libexec/gcc/x86_64-unknown-linux-gnu/5.2.1/lto-wrapper
Target: x86_64-unknown-linux-gnu
Configured with: /home/sss/gcc/gcc/configure --prefix=/usr/local/gcc
--enable-threads=posix --enable-long-long --enable-languages=c,c++,fortran
Thread model: posix
gcc version 5.2.1 20151002 (GCC) 
$ gcc -c -O2 x.c
x.c: In function ‘demangle_qualified’:
x.c:6:9: warning: implicit declaration of function ‘isdigit’
[-Wimplicit-function-declaration]
    if (!isdigit (*p))
         ^
x.c:1:5: internal compiler error: in duplicate_ssa_name_range_info, at
tree-ssanames.c:506
 int demangle_qualified (const char* mangled)
     ^
0xb29f14 duplicate_ssa_name_range_info(tree_node*, value_range_type,
range_info_def*)
        /home/sss/gcc/gcc/gcc/tree-ssanames.c:506
0xacdff3 eliminate_dom_walker::before_dom_children(basic_block_def*)
        /home/sss/gcc/gcc/gcc/tree-ssa-pre.c:4151
0xe9d5e1 dom_walker::walk(basic_block_def*)
        /home/sss/gcc/gcc/gcc/domwalk.c:188
0xacc23b eliminate
        /home/sss/gcc/gcc/gcc/tree-ssa-pre.c:4540
0xad405e execute
        /home/sss/gcc/gcc/gcc/tree-ssa-pre.c:4894
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.
$ 


tree-ssanames.c:506 is this line:

  gcc_assert (!SSA_NAME_ANTI_RANGE_P (name));

The last update i did from gcc-5-branch was about a month ago,
and i did not see this crash with that version.

thanks,
sss