[Bug ada/65519] Unable to coalesce ssa_names 2 and 87 which are marked as MUST COALESCE if ZCX_By_Default is set False

[syq at debian dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65519

--- Comment #1 from YunQiang Su <syq at debian dot org> ---
It only fails when using -O2 +, while
build successfully when using -O1.