[Bug c++/34021] New: Segmentation fault in G++ 4.1.3 with -O2

[chuongdo at cs dot stanford dot edu]

The following C++ code crashes when compiling with G++ 4.1.3, even though it is
perfectly valid C++.  To reproduce the bug, simply compile the program with -O2
and run it.

EXECUTION:

chuongdo@intron:~/cs/temp$ g++ -v
Using built-in specs.
Target: i486-linux-gnu
Configured with: ../src/configure -v
--enable-languages=c,c++,fortran,objc,obj-c++,treelang --prefix=/usr
--enable-shared --with-system-zlib --libexecdir=/usr/lib
--without-included-gettext --enable-threads=posix --enable-nls
--with-gxx-include-dir=/usr/include/c++/4.1.3 --program-suffix=-4.1
--enable-__cxa_atexit --enable-clocale=gnu --enable-libstdcxx-debug
--enable-mpfr --enable-checking=release i486-linux-gnu
Thread model: posix
gcc version 4.1.3 20070929 (prerelease) (Ubuntu 4.1.2-16ubuntu2)
chuongdo@intron:~/cs/temp$ g++ -o a a.cc -O2 -Wall
chuongdo@intron:~/cs/temp$ ./a
foo
Segmentation fault (core dumped)

CODE:

#include <vector>
#include <iostream>

struct A {
  std::vector<double> v, w;
  A();    
};

A::A() : v(2), w(2){
  std::cerr << "foo" << std::endl;

  for (int i = 0; i < 2; i++){
    for (int j = i+1; j < 2; j++){
      w[i] -= v[i];
      w[j] -= v[j];
    }
  }

}

int main (){
  A a;
  return 0;
}


-- 
           Summary: Segmentation fault in G++ 4.1.3 with -O2
           Product: gcc
           Version: 4.1.3
            Status: UNCONFIRMED
          Severity: critical
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: chuongdo at cs dot stanford dot edu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34021