https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127527
Bug ID: 127527
Summary: ICE: segfault in c_finish_bc_name on a malformed
switch/for/break sequence (named loops)
Product: gcc
Version: 17.0
Status: UNCONFIRMED
Keywords: error-recovery, ice-on-invalid-code
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: captainnemo9292 at gmail dot com
Target Milestone: ---
Target: x86_64-linux-gnu
The named-break/continue code introduced for C2Y named loops dereferences
a null pointer when the enclosing statement failed to parse:
void b() { switch case : for break a }
$ gcc -c t.c
t.c:1:19: error: expected '(' before 'case'
t.c:1:24: internal compiler error: Segmentation fault
c_finish_bc_name(unsigned long, tree_node*, bool)
c_parse_file()
https://godbolt.org/z/droP7YP9W
'break a' looks up the label 'a' in the enclosing loop/switch stack, but the
switch statement never got a body/condition, so the entry it finds is empty.
gcc trunk 17.0.0 20260920; gcc 13 (before named loops) only reports the
syntax errors.
