https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123344
Bug ID: 123344
Summary: ICE: Segmentation fault in tree_to_uhwi, at tree.cc
Product: gcc
Version: 15.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: 522024330006 at smail dot nju.edu.cn
Target Milestone: ---
Compiler Explorer: https://godbolt.org/z/baGhPbnro
struct S (containing flex[]) is the first member of struct T, followed by a
pointer struct T *t.This creates an indeterminate memory layout leading to the
crash.
Program:
```c
#include <stdio.h>
struct S {
int s;
char flex[];
};
struct T {
struct S s;
struct T *t;
};
void foo() {
static struct T t1 = {{42, "hello"}, NULL};
t1.t = &t1;
}
```
Traceback:
```
internal compiler error: in tree_to_uhwi, at tree.cc:6599
43 | }
| ^
0x569ce3c internal_error(char const*, ...)
/workspace/install/gcc/src/gcc/gcc/diagnostic-global-context.cc:517
0x563a4de fancy_abort(char const*, int, char const*)
/workspace/install/gcc/src/gcc/gcc/diagnostic.cc:1749
0x2845680 tree_to_uhwi(tree_node const*)
/workspace/install/gcc/src/gcc/gcc/tree.cc:6599
0x295c7e0 check_string_literal
/workspace/install/gcc/src/gcc/gcc/varasm.cc:5339
0x295e6de output_constant
/workspace/install/gcc/src/gcc/gcc/varasm.cc:5582
0x29602b4 output_constructor_regular_field
/workspace/install/gcc/src/gcc/gcc/varasm.cc:5854
0x29614fd output_constructor
/workspace/install/gcc/src/gcc/gcc/varasm.cc:6120
0x295eb1b output_constant
/workspace/install/gcc/src/gcc/gcc/varasm.cc:5611
0x29602b4 output_constructor_regular_field
/workspace/install/gcc/src/gcc/gcc/varasm.cc:5854
0x29614fd output_constructor
/workspace/install/gcc/src/gcc/gcc/varasm.cc:6120
0x295eb1b output_constant
/workspace/install/gcc/src/gcc/gcc/varasm.cc:5611
0x294a6ae assemble_variable_contents
/workspace/install/gcc/src/gcc/gcc/varasm.cc:2440
0x294b9f4 assemble_variable(tree_node*, int, int, int)
/workspace/install/gcc/src/gcc/gcc/varasm.cc:2619
0x298191c varpool_node::assemble_decl()
/workspace/install/gcc/src/gcc/gcc/varpool.cc:596
0x2982983 symbol_table::output_variables()
/workspace/install/gcc/src/gcc/gcc/varpool.cc:764
0x1364a8a symbol_table::compile()
/workspace/install/gcc/src/gcc/gcc/cgraphunit.cc:2421
0x1365437 symbol_table::finalize_compilation_unit()
/workspace/install/gcc/src/gcc/gcc/cgraphunit.cc:2607
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
```
