[Bug c++/35652] New: Location information incorrect on string bounds warning

[simon_baldwin at yahoo dot com]

The following demonstrates a location error in a string bounds warning message:

$ cat /tmp/c.cc
#include <string>
int main() {
  // blank line padding, could also be code...
  //
  //
  //
  //
  //
  //
  //
  //
  //
  std::string s = "";
  s += 'x' + "y";  // bogus
}

$ g++ -O2 -c /tmp/c.cc
/tmp/c.cc: In function 'int main()':
/tmp/c.cc:2: warning: offset outside bounds of constant string
/tmp/c.cc:2: warning: offset outside bounds of constant string
/tmp/c.cc:2: warning: offset outside bounds of constant string
/tmp/c.cc:2: warning: offset outside bounds of constant string
/tmp/c.cc:2: warning: offset outside bounds of constant string
/.../i686-unknown-linux-gnu/include/c++/4.3.0/bits/char_traits.h:262: warning:
offset outside bounds of constant string
/.../i686-unknown-linux-gnu/include/c++/4.3.0/bits/char_traits.h:262: warning:
offset outside bounds of constant string

The erroneous line is line 14, but g++ reports the problem (multiple times) at
line 2 and in an STL header file.  The same behavior occurs in g++ 4.2.1,
4.1.1, 4.0.3, and 4.0.2.  It does not occur in gcc 3.4.5.

Also, there is no warning emitted with -O0, for some reason.


-- 
           Summary: Location information incorrect on string bounds warning
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: simon_baldwin at yahoo dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35652