[Bug target/29006] New: Incorrect zeroing of unaligned 64-bit fields on MIPS targets

[rsandifo at gcc dot gnu dot org]

gcc will use swl/swr instead of sdl/sdr to zero an unaligned
64-bit field.  This can be seem with a testcase like:

struct __attribute__((__packed__)) s { char c; unsigned long long x; };
void __attribute__((__noinline__)) foo (struct s *s) { s->x = 0; }
int main (void) { struct s s = { 1, ~0ULL }; foo (&s); return s.x != 0; }


-- 
           Summary: Incorrect zeroing of unaligned 64-bit fields on MIPS
                    targets
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rsandifo at gcc dot gnu dot org
GCC target triplet: mipsisa64-elf


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29006