[Bug target/33381] New: [4.2 regression] miscompilation casting signed long to void*

[debian-gcc at lists dot debian dot org]

[forwarded from http://bugs.debian.org/440545]

seen with 4.2 branch 20070902, works with 4,1 branch and trunk

  Matthias

Output from attached program, if compiled with optimization level -O2:
>From 0 to 2:
 0 - In: -1, -1 (0xffffffffffffffff), Out: -1
 1 - In: 0, 0 (0xffffffffffffffff), Out: 0
 2 - In: 1, 1 (0xffffffffffffffff), Out: 1
>From 1 to 3:
 1 - In: 0, 0 ((nil)), Out: 0
 2 - In: 1, 1 (0x1), Out: 1
 3 - In: 2, 2 (0x2), Out: 2

 Should be
>From 0 to 2:
 0 - In: -1, -1 (0xffffffffffffffff), Out: -1
 1 - In: 0, 0 ((nil)), Out: 0
 2 - In: 1, 1 (0x1), Out: 1
>From 1 to 3:
 1 - In: 0, 0 ((nil)), Out: 0
 2 - In: 1, 1 (0x1), Out: 1
 3 - In: 2, 2 (0x2), Out: 2


#include <assert.h>
#include <stdio.h>
#include <stdlib.h>

int main()
{
  int i = 0;

  printf("From 0 to 2:\n");
  for (i = 0; i < 3; i++) {
    int iin = i - 1;
    signed long lin = iin;
    void *pin = (void *) lin;
    signed long iout = (signed long) pin;

    printf(" %d - In: %d, %ld (%p), Out: %ld\n", i, iin, lin, pin, iout);
  }

  printf("From 1 to 3:\n");
  for (i = 1; i < 4; i++) {
    int iin = i - 1;
    signed long lin = iin;
    void *pin = (void *) lin;
    signed long iout = (signed long) pin;

    printf(" %d - In: %d, %ld (%p), Out: %ld\n", i, iin, lin, pin, iout);
  }

  return EXIT_SUCCESS;
}


-- 
           Summary: [4.2 regression] miscompilation casting signed long to
                    void*
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: debian-gcc at lists dot debian dot org
GCC target triplet: x64_86-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33381