[Bug driver/117992] gcc -flto -fharden leads to warning

[uwu at icenowy dot me]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117992

--- Comment #11 from Icenowy Zheng <uwu at icenowy dot me> ---
Checked gcc -v, there's really enable-default-pie, and in the output of "gcc
main.c -fhardened -O2 -flto -v", the COLLECT_GCC_OPTIONS lists really include
"-pie".

Thus the explanation by Ruoyao looks reasonable. Thanks.