https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101574
Thomas Schwinge <tschwinge at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |marxin at gcc dot gnu.org,
| |msebor at gcc dot gnu.org
Keywords| |GC
--- Comment #6 from Thomas Schwinge <tschwinge at gcc dot gnu.org> ---
Short summary: I ran into an unexpected '0xa5a5a5a5' in
'gcc/warning-control.cc', and a search through email archives pointed me to
PR101292, PR101204, which superficially indeed do look similar.
Anybody got a good suggestion about how to proceed here?
---
(gdb) break c-common.c:3633
Breakpoint 3 at 0xea31b5: file [...]/source-gcc/gcc/c-family/c-common.c,
line 3633.
(gdb) r
[...]
Breakpoint 3, c_common_truthvalue_conversion (location=2147537812,
expr=0x7ffff3f10550) at [...]/source-gcc/gcc/c-family/c-common.c:3635
3635 if (!warning_suppressed_p (expr, OPT_Wparentheses)
(gdb) c
Continuing.
Breakpoint 3, c_common_truthvalue_conversion (location=2147537812,
expr=0x7ffff3f105f0) at [...]/source-gcc/gcc/c-family/c-common.c:3635
3635 if (!warning_suppressed_p (expr, OPT_Wparentheses)
(gdb) c
Continuing.
Breakpoint 3, c_common_truthvalue_conversion (location=2147537909,
expr=0x7ffff3f14be0) at [...]/source-gcc/gcc/c-family/c-common.c:3635
3635 if (!warning_suppressed_p (expr, OPT_Wparentheses)
(gdb) s
warning_suppressed_p (expr=0x7ffff3f14be0, opt=OPT_Wparentheses) at
[...]/source-gcc/gcc/warning-control.cc:119
119 const nowarn_spec_t *spec = get_nowarn_spec (expr);
(gdb) s
get_nowarn_spec (expr=0x7ffff3f14be0) at
[...]/source-gcc/gcc/warning-control.cc:92
92 const key_type_t key = convert_to_key (expr);
(gdb) call debug_tree(expr)
<modify_expr 0x7ffff3f14be0
type <integer_type 0x7ffff65fc690 unsigned int public unsigned type_6
SI
size <integer_cst 0x7ffff65ff120 constant 32>
unit-size <integer_cst 0x7ffff65ff138 constant 4>
align:32 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7ffff65fc690 precision:32 min <integer_cst 0x7ffff65ff150 0> max <integer_cst
0x7ffff65ff108 4294967295>
pointer_to_this <pointer_type 0x7ffff660c348> reference_to_this
<reference_type 0x7ffff3ce9d20>>
side-effects
arg:0 <view_convert_expr 0x7ffff2f46780 type <integer_type
0x7ffff65fc690 unsigned int>
tree_2
arg:0 <view_convert_expr 0x7ffff2f467a0 type <integer_type
0x7ffff65fc690 unsigned int>
public arg:0 <var_decl 0x7ffff608e6c0 i>
[...]/source-gcc/gcc/lra-lives.c:304:3 start:
[...]/source-gcc/gcc/lra-lives.c:304:3 finish:
[...]/source-gcc/gcc/lra-lives.c:304:3>
[...]/source-gcc/gcc/lra-lives.c:304:3 start:
[...]/source-gcc/gcc/lra-lives.c:304:3 finish:
[...]/source-gcc/gcc/lra-lives.c:304:3>
arg:1 <call_expr 0x7ffff30edd58 type <integer_type 0x7ffff65fc690
unsigned int>
side-effects nothrow
fn <addr_expr 0x7ffff2f467c0 type <pointer_type 0x7ffff246bc78>
constant arg:0 <function_decl 0x7ffff2794c00
sparseset_iter_elm>>
arg:0 <view_convert_expr 0x7ffff2f467e0 type <pointer_type
0x7ffff278eb28 sparseset>
public arg:0 <var_decl 0x7ffff60426c0 pseudos_live>
[...]/source-gcc/gcc/lra-lives.c:304:3 start:
[...]/source-gcc/gcc/lra-lives.c:304:3 finish:
[...]/source-gcc/gcc/lra-lives.c:304:3>
[...]/source-gcc/gcc/lra-lives.c:304:3 start:
[...]/source-gcc/gcc/lra-lives.c:304:3 finish:
[...]/source-gcc/gcc/lra-lives.c:304:3>
[...]/source-gcc/gcc/lra-lives.c:304:3 start:
[...]/source-gcc/gcc/lra-lives.c:304:3 finish:
[...]/source-gcc/gcc/lra-lives.c:304:3>
(gdb) n
94 if (!get_no_warning_bit (expr) || !key)
(gdb) print key
$4 = 2147537909
(gdb) print/x key
$5 = 0x8000d3f5
(gdb) s
get_no_warning_bit (expr=0x7ffff3f14be0) at
[...]/source-gcc/gcc/warning-control.cc:40
40 return expr->base.nowarning_flag;
(gdb) finish
Run till exit from #0 get_no_warning_bit (expr=0x7ffff3f14be0) at
[...]/source-gcc/gcc/warning-control.cc:40
0x0000000001d18699 in get_nowarn_spec (expr=0x7ffff3f14be0) at
[...]/source-gcc/gcc/warning-control.cc:94
94 if (!get_no_warning_bit (expr) || !key)
Value returned is $6 = true
(gdb) n
97 return nowarn_map ? nowarn_map->get (key) : NULL;
(gdb) print nowarn_map
$7 = (xint_hash_map_t *) 0x7ffff675ae10
(gdb) finish
Run till exit from #0 get_nowarn_spec (expr=0x7ffff3f14be0) at
[...]/source-gcc/gcc/warning-control.cc:97
0x0000000001d18764 in warning_suppressed_p (expr=0x7ffff3f14be0,
opt=OPT_Wparentheses) at [...]/source-gcc/gcc/warning-control.cc:119
119 const nowarn_spec_t *spec = get_nowarn_spec (expr);
Value returned is $8 = (nowarn_spec_t *) 0x7ffff65c66d4
(gdb) print/x *$8
$9 = {m_bits = 0xa5a5a5a5}
(This is what then causes the spurious diagnostic; in a "non-faulting" build,
this is 'm_bits = 2'.)
