https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116015
Bug ID: 116015
Summary: ICE in replace_placeholders_r for simple default
member initializer
Product: gcc
Version: 14.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: pieter.p.dev at outlook dot com
Target Milestone: ---
Created attachment 58713
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58713&action=edit
Output from -freport-bug
G++ crashes when using member variables in the default initializer for another
member. Minimal example:
struct MatrixLayout {
int rows = 0;
int outer_stride = rows;
};
struct Matrix {
Matrix(MatrixLayout) {}
};
struct Widget {
int n = 5;
Matrix A{{.rows = n}};
};
int main() {
Widget w{};
}
All versions of GCC between at least 5.1 and 14.1 seem to be affected:
- 5.1: https://godbolt.org/z/1PKx8djxG
- 14.1: https://godbolt.org/z/1eeEcYoqd
- trunk: https://godbolt.org/z/7j7n38ohh
(8d6498f0d772775ad09d7d9e14f491a306e5f853)
Possibly related to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100252#c5.
To the best of my knowledge, the source code is valid C++20 (and valid C++11
without the designated initializer), and Clang and MSVC compile the same code
without issues.
Output from GCC 14.1:
ice.cpp: In function 'int main()':
ice.cpp:16:14: internal compiler error: in replace_placeholders_r, at
cp/tree.cc:3414
16 | Widget w{};
| ^
0x732cae replace_placeholders_r
cp/tree.cc:3414
0x11be9e3 walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*,
void*), void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*,
tree_node* (*)(tree_node**, int*, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*))
tree.cc:11429
0x11bef2f walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*,
void*), void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*,
tree_node* (*)(tree_node**, int*, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*))
tree.cc:11663
0x960b0c replace_placeholders_r
cp/tree.cc:3459
0x11be9e3 walk_tree_1(tree_node**, tree_node* (*)(tree_node**, int*,
void*), void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*,
tree_node* (*)(tree_node**, int*, tree_node* (*)(tree_node**, int*, void*),
void*, hash_set<tree_node*, false, default_hash_traits<tree_node*> >*))
tree.cc:11429
0x95d985 replace_placeholders(tree_node*, tree_node*, bool*)
cp/tree.cc:3497
0x7e0dde cp_gimplify_init_expr
cp/cp-gimplify.cc:339
0x7e0dde cp_gimplify_expr(tree_node**, gimple**, gimple**)
cp/cp-gimplify.cc:652
0xc139b8 gimplify_expr(tree_node**, gimple**, gimple**, bool
(*)(tree_node*), int)
gimplify.cc:17790
0xc17616 gimplify_stmt(tree_node**, gimple**)
gimplify.cc:7578
0xc19632 gimplify_and_add(tree_node*, gimple**)
gimplify.cc:515
0xc19632 internal_get_tmp_var
gimplify.cc:674
0xc13c7b gimplify_expr(tree_node**, gimple**, gimple**, bool
(*)(tree_node*), int)
gimplify.cc:18908
0xc1b564 gimplify_expr
gimplify.cc:18953
0xc1b564 gimplify_arg(tree_node**, gimple**, unsigned int, bool)
gimplify.cc:3779
0xc1da17 gimplify_call_expr
gimplify.cc:4064
0xc15ac2 gimplify_expr(tree_node**, gimple**, gimple**, bool
(*)(tree_node*), int)
gimplify.cc:17853
0xc17616 gimplify_stmt(tree_node**, gimple**)
gimplify.cc:7578
0xc15607 gimplify_cleanup_point_expr
gimplify.cc:7316
0xc15607 gimplify_expr(tree_node**, gimple**, gimple**, bool
(*)(tree_node*), int)
gimplify.cc:18277
