[Bug c++/35730] New: ICE on valid code convert_move expr.c:373

[Bug c++/35730] New: ICE on valid code convert_move expr.c:373

[davids at webmaster dot com]

The following code produces an ICE with GCC-4.3.0 when compiled with g++ and
-O. Removing -O or using gcc removes the ICE.

#include <string.h>
int moo(void) 
{
 unsigned char msg[] = { 0, 0 };
 unsigned char data[2];
 memcpy(data, msg, sizeof (msg));
 return memcmp(data, msg, sizeof (data)) != 0;
}

Also, changing msg's declaration from "msg[]" to "msg[2]" avoids the ICE.

g++430 test.c -c -O
test.c: In function 'int moo()':
test.c:6: internal compiler error: in convert_move, at expr.c:373
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions

Using gcc430, g++423, or g++412, the code compiles fine. Of the builds I
tested, only g++ 4.3.0 has the problem.


-- 
           Summary: ICE on valid code convert_move expr.c:373
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: davids at webmaster dot com
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35730

[Bug c++/35730] ICE on valid code convert_move expr.c:373

[davids at webmaster dot com]

------- Comment #1 from davids at webmaster dot com  2008-03-28 09:24 -------
#include <string.h>
int moo(void) 
{
 unsigned char msg1[] = { 0, 0 };
 unsigned char msg2[] = { 0, 0 };
 memcpy(msg1, msg2, 2);
 return memcmp(msg1, msg2, 2) != 0;
}

With this code, changing the sizes in both memcpy and memcmp from '2' to '1'
makes the problem go away. So does changing both arrays from '{ 0, 0 }' to { 0,
0, 0 }'. So maybe it's an off-by-one?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35730

[Bug c++/35730] ICE on valid code convert_move expr.c:373

[rguenth at gcc dot gnu dot org]

------- Comment #2 from rguenth at gcc dot gnu dot org  2008-03-28 10:30 -------


*** This bug has been marked as a duplicate of 35526 ***


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |DUPLICATE


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35730