https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120898
Bug ID: 120898
Summary: ICE at -O2 calling function with old-style definition
taking a VLA parameter
Product: gcc
Version: 15.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: stephenheumann at gmail dot com
Target Milestone: ---
Compiling this with -O2:
```
int foo(a,b)
int a;
int b[][a];
{
return sizeof(b[1]);
}
int main(void) {
int c[4][4];
foo(4,c);
}
```
gives the following:
<source>: In function 'foo':
<source>:1:5: warning: old-style function definition [-Wold-style-definition]
1 | int foo(a,b)
| ^~~
during GIMPLE pass: einline
<source>: In function 'main':
<source>:10:9: internal compiler error: in make_ssa_name_fn, at
tree-ssanames.cc:355
10 | foo(4,c);
| ^~~~~~~~
0x20bd0f5 diagnostic_context::diagnostic_impl(rich_location*,
diagnostic_metadata const*, diagnostic_option_id, char const*, __va_list_tag
(*) [1], diagnostic_t)
???:0
0x20ce646 internal_error(char const*, ...)
???:0
0x7a56c6 fancy_abort(char const*, int, char const*)
???:0
0xe8f0bf copy_tree_body_r(tree_node**, int*, void*)
???:0
0x11391b2 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*> >*))
???:0
0x1139391 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*> >*))
???:0
0xe8a88b remap_type(tree_node*, copy_body_data*)
???:0
0xe8a88b remap_type(tree_node*, copy_body_data*)
???:0
0xe97d59 optimize_inline_calls(tree_node*)
???:0
0x1f0f07e early_inliner(function*)
???:0
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.
(The ICE still appears if an older standard where old-style definitions are
allowed is specified.)
Godbolt link: https://godbolt.org/z/66Ke7fMxo
>From checking different versions on Godbolt, this appears to be a regression in
GCC 14.
