https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100314
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Version|unknown |12.0
Last reconfirmed|2021-09-25 00:00:00 |2022-1-11
CC| |hubicka at gcc dot gnu.org,
| |jamborm at gcc dot gnu.org
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
the key is to notice that 'a' is not modified and thus zero and propagate that
to 'd'. With -O3 IPA figures out 'a' is not modified but that isn't taken into
account by IPA CP which sees
a.0_1 = a;
d (a.0_1);
with -O1 we happen to inline everything during IPA and nothing early while
with -O3 'e' is early inlined into 'd' (but not d into main) and IPA
refuses to inline d into main:
t.c:18:3: missed: not inlinable: main/7 -> d/6, --param
large-stack-frame-growth limit reached
sth is off with the stack limit I guess, maybe it's not cummulated correctly
at -O1.
