https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86840
Bug ID: 86840
Summary: __attribute__((optimize("exceptions"))) is silently
ignored
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: vries at gcc dot gnu.org
Target Milestone: ---
Consider test.c:
...
void a (void);
void do_cleanup (void *p);
void
#ifdef E
__attribute__((optimize("exceptions")))
#endif
b (void)
{
int c __attribute__((cleanup(do_cleanup)));
a();
}
...
When enabling exceptions, an exception table is generated:
...
$ gcc test.c -o- -S -O2 -fexceptions | grep -c "\.gcc_except_table"
2
...
And when disabling exceptions, it's not:
...
$ gcc test.c -o- -S -O2 -fno-exceptions | grep -c "\.gcc_except_table"
0
...
When enabling exceptions using the attribute on function b, no exception table
is generated:
...
$ gcc test.c -o- -S -O2 -fno-exceptions -DE | grep -c "\.gcc_except_table"
0
...
This should have a warning "attribute ignored", and/or document this more
clearly in the documentation of fexceptions and/or the optimize attribute.
