[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219 Patrick Palka changed: What|Removed |Added Target Milestone|--- |12.0 CC||ppalka at gcc dot gnu.org
[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219 Sergei Trofimovich changed: What|Removed |Added Resolution|--- |FIXED Status|NEW |RESOLVED --- Comment #10 from Sergei Trofimovich --- Should be fixed in 10.0
[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219
--- Comment #9 from CVS Commits ---
The master branch has been updated by Sergei Trofimovich :
https://gcc.gnu.org/g:27a1fb385b7fe706f05608e53f3e91d7d3442b8b
commit r12-2883-g27a1fb385b7fe706f05608e53f3e91d7d3442b8b
Author: Sergei Trofimovich
Date: Fri Aug 6 16:14:16 2021 +0100
c++: fix ptrmemfunc template instantiation [PR101219]
r12-1804 ("cp: add support for per-location warning groups.") among other
things removed warning suppression from a few places including ptrmemfuncs.
This exposed a bug in warning detection code as a reference to missing
BINFO (it's intentionally missing for ptrmemfunc types):
crash_signal
gcc/toplev.c:328
perform_or_defer_access_check(tree_node*, tree_node*, tree_node*, int,
access_failure_info*)
gcc/cp/semantics.c:490
finish_non_static_data_member(tree_node*, tree_node*, tree_node*)
gcc/cp/semantics.c:2208
...
The change special cases ptrmemfuncs in templace substitution by using
build_ptrmemfunc_access_expr() instead of finish_non_static_data_member().
gcc/cp/ChangeLog:
PR c++/101219
* pt.c (tsubst_copy_and_build): Use build_ptrmemfunc_access_expr
to construct ptrmemfunc expression instantiation.
gcc/testsuite/ChangeLog:
PR c++/101219
* g++.dg/warn/pr101219.C: New test.
[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219 --- Comment #8 from Sergei Trofimovich --- Proposed simplistic change as https://gcc.gnu.org/pipermail/gcc-patches/2021-July/575867.html
[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219 --- Comment #7 from Martin Sebor --- Thanks for tracking down the change that triggers the ICE! I removed the suppression in a few cases where it served no apparent purpose (wasn't necessary to suppress warnings exercised by the test suite). This was not the primary but a secondary goal of the patch. Jason is probably in the best position to answer your questions, as well as why the removed suppression was there to begin with and whether it should be restored.
[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219
--- Comment #6 from Sergei Trofimovich ---
gcc internals doc says that binfo should be attached to every class/struct
(RECORD). I'm not sure if this case qualifies. Maybe?
Why this crash happens mechanically? I skimmed through commit 65870e75616ee43
("cp: add support for per-location warning groups.") and found a few places
where warning suppression was removed.
Returning the one around ptrmem prevents the crash from happening:
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -3326,7 +3326,9 @@ build_ptrmemfunc_access_expr (tree ptrmem, tree
member_name)
member = DECL_CHAIN (member))
if (DECL_NAME (member) == member_name)
break;
- return build_simple_component_ref (ptrmem, member);
+ tree r = build_simple_component_ref (ptrmem, member);
+ suppress_warning(r);
+ return r;
}
/* Given an expression PTR for a pointer, return an expression
[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219 --- Comment #5 from Sergei Trofimovich --- build_ptrmemfunc_type() creates fresh RECORD_TYPE for (each?) __pfn. Should it probably populate TYPE_BINFO(t) as well? https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/cp/decl.c;h=01d64a16125ec0bb8e3798136472c30f475f96a2;hb=HEAD#l10526
[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219
--- Comment #4 from Sergei Trofimovich ---
Got the same mednafen crash today. Poked slightly at the context in gdb.
>From what I understand the crash happens when analysing statement `void
(PCEFast_PSG::*ch_0)(int, int *);`. There is no access to the any object field
implied by `TYPE_BINFO (access_type)`. Or is there? Should it refer to `class
PCEFast_PSG`?
(gdb) fr 1
#1 0x0079ff83 in finish_non_static_data_member (decl=0x77652a18,
object=0x77796860, qualifying_scope=0x0) at
/home/slyfox/dev/git/gcc/gcc/cp/semantics.c:2208
2208 perform_or_defer_access_check (TYPE_BINFO (access_type), decl,
(gdb) list
2203 QUALIFYING_SCOPE is also non-null. */
2204 else
2205{
2206 volatile tree access_type = TREE_TYPE (object);
2207
2208 perform_or_defer_access_check (TYPE_BINFO (access_type), decl,
2209 decl, tf_warning_or_error);
2210
2211 /* If the data member was named `C::M', convert `*this' to `C'
2212 first. */
(gdb) call print_tree(object)
No symbol "print_tree" in current context.
(gdb) call debug_tree(object)
unit-size
align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x777a1bd0
fields
unsigned nonaddressable DI psg.cpp.cpp:5:39
size
unit-size
align:64 warn_if_not_align:0 offset_align 128
offset
bit-offset context
chain >
ptrmemfunc fn type
public unsigned type_6 DI size
unit-size
align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x777a1b28>
chain >
constant>
(gdb) call debug_tree(access_type)
constant 128>
unit-size constant 16>
align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x777a1bd0
fields
public unsigned type_6 DI
size
unit-size
align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x777a1b28>
unsigned nonaddressable DI psg.cpp.cpp:5:39 size unit-size
align:64 warn_if_not_align:0 offset_align 128
offset
bit-offset context
chain
nonaddressable DI psg.cpp.cpp:5:39 size unit-size
align:64 warn_if_not_align:0 offset_align 128 offset bit-offset context
>> ptrmemfunc fn type
chain >
[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219
--- Comment #3 from Martin Sebor ---
The code fails in the assert below where binfo is null. The full stack trace
follows. The difference is that before r12-1804 warn_for_null_address() would
return without doing anything because TREE_NO_WARNING(op) was 1. r12-1804
changed the TREE_NO_WARNING(op) test to warning_suppressed_p (op,
OPT_Waddress)) which returns false. The no-warning bit on OP is also clear so
something has caused it to not be set. Possibly a subtle difference in the
location value. Whatever has caused the change, it seems like the root cause
of the ICE is something else (unless the front end somehow relies on the
no-warning bit to also mean something else than just "disable warnings").
bool
perform_or_defer_access_check (tree binfo, tree decl, tree diag_decl,
tsubst_flags_t complain,
access_failure_info *afi)
{
int i;
deferred_access *ptr;
deferred_access_check *chk;
/* Exit if we are in a context that no access checking is performed. */
if (deferred_access_no_check)
return true;
gcc_assert (TREE_CODE (binfo) == TREE_BINFO);
0x1717bc8 crash_signal
/ssd/src/gcc/master/gcc/toplev.c:328
0xdf00fb perform_or_defer_access_check(tree_node*, tree_node*, tree_node*, int,
access_failure_info*)
/ssd/src/gcc/master/gcc/cp/semantics.c:490
0xdf6a7d finish_non_static_data_member(tree_node*, tree_node*, tree_node*)
/ssd/src/gcc/master/gcc/cp/semantics.c:2208
0xda8762 tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool,
bool)
/ssd/src/gcc/master/gcc/cp/pt.c:20568
0xd5d6cc instantiate_non_dependent_expr_internal(tree_node*, int)
/ssd/src/gcc/master/gcc/cp/pt.c:6323
0xad622f fold_non_dependent_expr_template
/ssd/src/gcc/master/gcc/cp/constexpr.c:7604
0xad6585 fold_non_dependent_expr(tree_node*, int, bool, tree_node*)
/ssd/src/gcc/master/gcc/cp/constexpr.c:7661
0xbda7c4 fold_for_warn(tree_node*)
/ssd/src/gcc/master/gcc/cp/expr.c:409
0xe67e56 warn_for_null_address
/ssd/src/gcc/master/gcc/cp/typeck.c:4453
0xe6a880 cp_build_binary_op(op_location_t const&, tree_code, tree_node*,
tree_node*, int)
/ssd/src/gcc/master/gcc/cp/typeck.c:5169
0xe6b0ff cp_build_binary_op(op_location_t const&, tree_code, tree_node*,
tree_node*, int)
/ssd/src/gcc/master/gcc/cp/typeck.c:5357
0xa59d4c build_new_op_1
/ssd/src/gcc/master/gcc/cp/call.c:6760
0xa59e57 build_new_op(op_location_t const&, tree_code, int, tree_node*,
tree_node*, tree_node*, tree_node**, int)
/ssd/src/gcc/master/gcc/cp/call.c:6806
0xe6774c build_x_binary_op(op_location_t const&, tree_code, tree_node*,
tree_code, tree_node*, tree_code, tree_node**, int)
/ssd/src/gcc/master/gcc/cp/typeck.c:4330
0xcd6d2c cp_parser_binary_expression
/ssd/src/gcc/master/gcc/cp/parser.c:10023
0xcd7229 cp_parser_assignment_expression
/ssd/src/gcc/master/gcc/cp/parser.c:10163
0xcd7608 cp_parser_expression
/ssd/src/gcc/master/gcc/cp/parser.c:10331
0xcdb75c cp_parser_expression_statement
/ssd/src/gcc/master/gcc/cp/parser.c:12075
0xcdafe1 cp_parser_statement
/ssd/src/gcc/master/gcc/cp/parser.c:11871
0xcdbd17 cp_parser_statement_seq_opt
/ssd/src/gcc/master/gcc/cp/parser.c:12223
[Bug c++/101219] [12 Regression] ice in perform_or_defer_access_check since r12-1804-g65870e75616ee435
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101219 Martin Liška changed: What|Removed |Added Last reconfirmed||2021-06-28 Summary|ice in |[12 Regression] ice in |perform_or_defer_access_che |perform_or_defer_access_che |ck |ck since ||r12-1804-g65870e75616ee435 CC||marxin at gcc dot gnu.org, ||msebor at gcc dot gnu.org Status|UNCONFIRMED |NEW Ever confirmed|0 |1 --- Comment #2 from Martin Liška --- Confirmed, started with r12-1804-g65870e75616ee435.
