https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108616
Bug ID: 108616
Summary: -Wanalyzer-allocation-size false negatives for use of
"alloca"
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: analyzer
Assignee: dmalcolm at gcc dot gnu.org
Reporter: dmalcolm at gcc dot gnu.org
Target Milestone: ---
Consider e.g. this bogusly-sized alloca:
#include <alloca.h>
#include <stdint.h>
int main(void)
{
int length = 99;
int32_t *arr = alloca(length);
return 0;
}
No warning is emitted for -Wanalyzer-allocation-size with -fanalyzer:
https://godbolt.org/z/eTjf6fTzE
unless we use -Wsystem-headers:
https://godbolt.org/z/oTKnG78ob
due to alloca being a macro inside a system header to __builtin_alloca.
We ought to warn for such cases; I have a fix under construction
