[Bug c++/60729] New: Compiler failure for combination of -ftrapv and -O3: compiler error: in prepare_cmp_insn

[rppawlo at sandia dot gov]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60729

            Bug ID: 60729
           Summary: Compiler failure for combination of -ftrapv and -O3:
                    compiler error: in prepare_cmp_insn
           Product: gcc
           Version: 4.8.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rppawlo at sandia dot gov

Created attachment 32514
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32514&action=edit
test file

Hi,

I'm running stock Ubuntu 13.10 and get a g++ compiler error when using a
certain commbination of compiler options.  

The attached file reproduces the bug:

*************************BEGIN FILE***********************

// This test generates an inernal compiler failure in g++ 4.8.1 on
// ubuntu 13.10.  The combination of -O3 and -ftrapv causes the issue.
// You can drop to -O2 or remove -ftrapv to fix.

// The following compile works:
// g++ -O3 -c test.cpp
// g++ -O2 -ftrapv -c test.cpp

// The following compile fails:
// g++ -ftrapv -O3 -c test.cpp

#include <cmath>

void doSomething(int dim, double *Y, double *A) 
{
  for (int k=0; k<dim; k++) 
    Y[k] += std::abs(A[k]);
}

*************************END FILE***********************

Here's the output:

rppawlo@drekar:~$ g++ -O3 -c test.cpp
rppawlo@drekar:~$ g++ -O2 -ftrapv -c test.cpp
rppawlo@drekar:~$ g++ -ftrapv -O3 -c test.cpp
test.cpp: In function ‘void doSomething(int, double*, double*)’:
test.cpp:17:27: internal compiler error: in prepare_cmp_insn, at optabs.c:4190
     Y[k] += std::abs(A[k]);
                           ^
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-4.8/README.Bugs> for instructions.
Preprocessed source stored into /tmp/cccvQgai.out file, please attach this to
your bugreport.
rppawlo@drekar:~$


Here's some info about my machine/environment:

rppawlo@drekar:~$ g++ --version
g++ (Ubuntu/Linaro 4.8.1-10ubuntu9) 4.8.1
Copyright (C) 2013 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

rppawlo@drekar:~$ uname -a
Linux drekar 3.11.0-18-generic #32-Ubuntu SMP Tue Feb 18 21:11:14 UTC 2014
x86_64 x86_64 x86_64 GNU/Linux