------- Additional Comments From steven at gcc dot gnu dot org 2005-01-27
21:26 -------
The lang hook thinks that with the 'const' the types of 'dest' and 'orig'
in may_propagate_copy are not the same.
(gdb)
2820 else if (!may_propagate_copy (op, val))
4: debug_generic_stmt (stmt) = # VUSE <TMT.0D.1464_10>;
D.1457_8 = *lengthp2D.1453_7;
void
(gdb) p may_propagate_copy (op, val)
$17 = 0 '\0'
In may_propagate_copy :
(gdb) next
111 if (mt_dest && mt_orig && mt_dest != mt_orig)
(gdb)
113 else if (!lang_hooks.types_compatible_p (type_d, type_o))
(gdb)
156 }
(gdb) p debug_generic_expr(dest)
lengthp2D.1453_7
$18 = void
(gdb) p debug_generic_expr(orig)
lengthpD.1449_3
(gdb) p lang_hooks.types_compatible_p (type_d, type_o)
$20 = 0
(gdb) p debug_tree (type_d)
<pointer_type 0x2a95a301a0
type <integer_type 0x2a95a300d0 unsigned int readonly unsigned SI
size <integer_cst 0x2a95890a80 constant invariant 32>
unit size <integer_cst 0x2a958905a0 constant invariant 4>
align 32 symtab 0 alias set -1 precision 32 min <integer_cst
0x2a95890b70 0> max <integer_cst 0x2a95890b40 4294967295>
pointer_to_this <pointer_type 0x2a95a301a0>>
unsigned DI
size <integer_cst 0x2a95890c30 type <integer_type 0x2a958965b0
bit_size_type> constant invariant 64>
unit size <integer_cst 0x2a95890c60 type <integer_type 0x2a958964e0 long
unsigned int> constant invariant 8>
align 64 symtab 0 alias set -1>
$21 = void
(gdb) p debug_tree (type_o)
<pointer_type 0x2a95988a90
type <integer_type 0x2a95896b60 unsigned int public unsigned SI
size <integer_cst 0x2a95890a80 constant invariant 32>
unit size <integer_cst 0x2a958905a0 constant invariant 4>
align 32 symtab 0 alias set -1 precision 32 min <integer_cst
0x2a95890b70 0> max <integer_cst 0x2a95890b40 4294967295>
pointer_to_this <pointer_type 0x2a95988a90>>
unsigned DI
size <integer_cst 0x2a95890c30 type <integer_type 0x2a958965b0
bit_size_type> constant invariant 64>
unit size <integer_cst 0x2a95890c60 type <integer_type 0x2a958964e0 long
unsigned int> constant invariant 8>
align 64 symtab 0 alias set -1>
$22 = void
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19659
