[Bug c/36521] Expression in for expression gets wrong value

[peter at xmos dot com]

--- Comment #1 from peter at xmos dot com  2008-06-13 08:52 ---
Created an attachment (id=15760)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=15760&action=view)
test.i


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36521

[Bug c/36521] New: Expression in for expression gets wrong value

[peter at xmos dot com]

The program below on gcc 4.1.2 prints:

> gcc4 test.c
> ./a.out
got 0
x
y
done

--
The program below on gcc 3.4.4 prints:

> gcc test.c
> ./a.out
got 0
x
y

and then locks up...

--

#include 

int main()
{
  unsigned int var102 = 1;
  int a = ( var102 >> 0x1eU & sizeof 290 );
  printf("got %d\n", a); fflush(stdout);

  for ( ; 0; )
  {}
  printf("x\n"); fflush(stdout);

  for ( ; a; )
  {}
  printf("y\n"); fflush(stdout);

  for ( ; ( var102 >> 0x1eU & sizeof 290 ); ) // Fails here
  {}
  printf("done\n");

  return 0;
}


-- 
   Summary: Expression in for expression gets wrong value
   Product: gcc
   Version: 3.4.4
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: c
    AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: peter at xmos dot com
 GCC build triplet: gcc (GCC) 3.4.4 (cygming special, gdc 0.12, using dmd
0.125)
  GCC host triplet: CYGWIN_NT-5.1 duane 1.5.24(0.156/4/2) 2007-01-31 10:57
i686 Cygw


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36521

[Bug c/36077] Expressions result is wrong

[peter at xmos dot com]

--- Comment #2 from peter at xmos dot com  2008-04-29 10:23 ---
Created an attachment (id=15544)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=15544&action=view)
test.i


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36077

[Bug c/36077] Expressions result is wrong

[peter at xmos dot com]

--- Comment #1 from peter at xmos dot com  2008-04-29 10:23 ---
Created an attachment (id=15543)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=15543&action=view)
test.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36077

[Bug c/36077] New: Expressions result is wrong

[peter at xmos dot com]

I am developing a test generator for in house compilers and have come across a
difference where gcc does not agree with our compilers or the Microsoft
compiler.

The result t1_2a of the expression is what differs between gcc and other
compilers.

This is on gcc (GCC) 3.4.6 20060404 (Red Hat 3.4.6-9), and does not matter what
the platform is.

Compiled with:

$ gcc4 test.c -o test.exe
$ ./test.exe
Error:
t1_2a 
t1_2b 22a8b02e
t1_2c 0

Working:
t2_2a 0
t2_2b 0

When compared to running on Visual Studio:

$ cl test.c
Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 14.00.50727.762 for
80x86
Copyright (C) Microsoft Corporation.  All rights reserved.

test.c
Microsoft (R) Incremental Linker Version 8.00.50727.762
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:test.exe
test.obj

$ ./test.exe
Error:
t1_2a 0
t1_2b 22a8b02e
t1_2c 0

Working:
t2_2a 0
t2_2b 0


-- 
   Summary: Expressions result is wrong
   Product: gcc
   Version: 4.1.2
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: peter at xmos dot com
 GCC build triplet: gcc version 4.1.2 20070626 (Red Hat 4.1.2-14)
  GCC host triplet: Linux 2.6.9-67.ELsmp #1 SMP Wed Nov 7 13:56:44 EST 2007
x86_64 x
GCC target triplet: Target: x86_64-redhat-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36077