This diagnostic triggers when -fsanitize=object-size is explicitly
specified but will be a no-op (i.e, at -O0).
This diagnostic should not fail a -Werror build because it's just an
explanatory note to the user. It's not always actionable.
For example, a user may not be able to simply disable object-size,
because they want it enabled in optimized builds.
rdar://42128447
llvm-svn: 336937
This check currently isn't able to diagnose any issues at -O0, not is it
likely to [1]. Disabling the check at -O0 leads to substantial compile
time and binary size savings.
[1] [cfe-dev] Disabling ubsan's object size check at -O0
Differential Revision: https://reviews.llvm.org/D34563
llvm-svn: 306181
Fangrui Song