[Bug c/96554] -Wall does not include -Wnull-dereference

[R.E.Wolff at BitWizard dot nl]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96554

--- Comment #4 from Roger Wolff <R.E.Wolff at BitWizard dot nl> ---
Update: LTO messes with the warning. When LTO is enabled, the warning from
-Wnull-dreference is suppressed.