Here's what the alias-7.c test looks like, after preprocessing:
> int foo __asm__ ("_" "foo") __attribute__((nocommon));
> extern __typeof (foo) bar __attribute__ ((weak, alias ("foo")));
>
> int
> main (void)
> {
> if (&foo != &bar || foo || bar)
> abort ();
> return bar;
> }
But here's how it compiles down using 4.5.0 on i686-pc-cygwin:
> alias-7.c.003t.original:
> ;; Function main (null)
> ;; enabled by -tree-original
>
>
> {
> if (1)
> {
> abort ();
> }
> return bar;
> }
I've established that fold_comparison is returning (integer_cst 1) for the
"&foo != &bar" test. In this clause,
> /* For non-equal bases we can simplify if they are addresses
> of local binding decls or constants. */
> else if (indirect_base0 && indirect_base1
> /* We know that !operand_equal_p (base0, base1, 0)
> because the if condition was false. But make
> sure two decls are not the same. */
> && base0 != base1
> && TREE_CODE (arg0) == ADDR_EXPR
> && TREE_CODE (arg1) == ADDR_EXPR
> && (((TREE_CODE (base0) == VAR_DECL
> || TREE_CODE (base0) == PARM_DECL)
> && (targetm.binds_local_p (base0)
> || CONSTANT_CLASS_P (base1)))
> || CONSTANT_CLASS_P (base0))
> && (((TREE_CODE (base1) == VAR_DECL
> || TREE_CODE (base1) == PARM_DECL)
> && (targetm.binds_local_p (base1)
> || CONSTANT_CLASS_P (base0)))
> || CONSTANT_CLASS_P (base1)))
> {
> if (code == EQ_EXPR)
> return omit_two_operands_loc (loc, type, boolean_false_node,
> arg0, arg1);
> else if (code == NE_EXPR)
> return omit_two_operands_loc (loc, type, boolean_true_node,
> arg0, arg1);
> }
it seems that i386_pe_binds_local_p is incorrectly returning true even for the
weak symbol. I have a patch.
--
Summary: FAIL: gcc.dg/alias-7.c execution test
Product: gcc
Version: 4.5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
AssignedTo: davek at gcc dot gnu dot org
ReportedBy: davek at gcc dot gnu dot org
GCC build triplet: i686-pc-cygwin
GCC host triplet: i686-pc-cygwin
GCC target triplet: i686-pc-cygwin
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43888
