https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98753
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|-Wfree-nonheap-object on |-Wfree-nonheap-object on
|Bison generated code |unreachable code with -O0
Known to fail| |11.0
Status|WAITING |NEW
Component|c++ |middle-end
--- Comment #7 from Martin Sebor <msebor at gcc dot gnu.org> ---
I can reproduce the warning with no optimization, thanks. At -O0, there are
three calls to free in the IL when the warning runs. The second one that
triggers it
# .MEM_218 = VDEF <.MEM_216>
free (yymsg.17_83);
is eliminated by copy propagation at -O1. It's not eliminated at -O0 because
the optimization isn't done then. So the ultimate root cause of the problem is
the same as in pr54202, except at -O0 (the test case there depends on
inlining).
It would be possible to disable the warning at -O0 to avoid this false positive
at the expense of some false negatives. I'm not sure that would be a good
solution based on a single report. If more bugs like this are reported we
might reconsider. Let me keep this bug open until then.
