[Bug c/43698] New: Invalid code when building gentoo pax-utils-0.1.19 with -Os optimizations

[siarhei dot siamashka at gmail dot com]

Tested with gcc-4.5.0-RC-20100406.tar.bz2

Reduced testcase:

/*********************************************************/
#include <stdio.h>
#include <stdint.h>

char do_reverse_endian = 0;

#  define bswap_32(x) \
                        ((((x) & 0xff000000) >> 24) | \
                         (((x) & 0x00ff0000) >>  8) | \
                         (((x) & 0x0000ff00) <<  8) | \
                         (((x) & 0x000000ff) << 24))

#define EGET(X) \
        (__extension__ ({ \
                uint64_t __res; \
                if (!do_reverse_endian) {    __res = (X); \
                } else if (sizeof(X) == 4) { __res = bswap_32((X)); \
                } \
                __res; \
        }))

void __attribute__((noinline)) X(char **phdr, char **data, int *phoff)
{
    *phdr = *data + EGET(*phoff);
}

int main()
{
    char *phdr;
    char *data = (char *)0x40164000;
    int phoff = 0x34;
    X(&phdr, &data, &phoff);
    printf("got %p (expecting 0x40164034)\n", phdr);
    return 0;
}
/*********************************************************/

# gcc -Os -o test test.c
# ./test
got 0x74164000 (expecting 0x40164034)


-- 
           Summary: Invalid code when building gentoo pax-utils-0.1.19 with
                    -Os optimizations
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: siarhei dot siamashka at gmail dot com
 GCC build triplet: armv7l-unknown-linux-gnueabi
  GCC host triplet: armv7l-unknown-linux-gnueabi
GCC target triplet: armv7l-unknown-linux-gnueabi


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43698