https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95857
Bug ID: 95857
Summary: Silencing an unused label warning with (void)&&label;
can make gcc segfault
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: pskocik at gmail dot com
Target Milestone: ---
Created attachment 48777
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48777&action=edit
preprocessed reproducer that crashes gcc >= 8.1 at -O2/-O3/-Os
In certain more complex contexts and with optimization on (>= -O2), silencing
-Wunused-label warnings with
(void)&&label; will make gcc segfault.
The attached example ( https://gcc.godbolt.org/z/iEhgL2 ) obtained with creduce
crashes gcc >= 8.1 when compiled at -O2/-O3/-Os.
I haven't observed the bug in older versions of gcc.
