[Bug target/21788] New: [x86_64] Wrong Code When Taking Address of Argument

["evandro at yahoo dot com" <gcc-bugzilla at gcc dot gnu dot org>]

Using -O2 or greater, when taking the address of an input argument results in
the wrong code.  For example:

int foo (double d)
{
  int *p = (int *) &d;

  return (*p);
}

With -O2 results in:

foo:
	movq	-8(%rsp), %eax
	ret

With -O1 results in:

foo:
	movsd	%xmm0, -8(%rsp)
	movq	-8(%rsp), %eax
	ret

-- 
           Summary: [x86_64] Wrong Code When Taking Address of Argument
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P2
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: evandro at yahoo dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21788