[Bug c/54950] New: Incorrect 32-bit moltiplication on m32c target

["m.galante at centrosistemi dot it" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54950

             Bug #: 54950
           Summary: Incorrect 32-bit moltiplication on m32c target
    Classification: Unclassified
           Product: gcc
           Version: 4.7.2
            Status: UNCONFIRMED
          Severity: critical
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: m.galante@centrosistemi.it


m32c-elf-gcc (GCC) 4.7.2 hosted on Windows XP.

This simple program:

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

void multiply(unsigned char byte)
{
  printf("%ld\n", 1000000L * byte);
}

main()
{
  multiply(2);
  return 0;
}
/**************** END ************/

produces the correct result (2000000) only when compiled with -O0:

m32c-elf-gcc -msim -mcpu=m32c -O0 -omul32.out mul32.c
m32c-elf-run mul32.out

If I compile with -O1, -O2, -O3 or -Os I get 33920, which is 2000000 truncated
to 16-bit.