C++ exit time destructor warning build option not working?

I have a c++ project that is giving this warning:
Declaration requires an exit-time destructor
I understand the warning, as it is on a singleton class.

However, in the build options under Apple Clang-Warnings-C++ I have the following
Exit-Time C++ Destructors set to No

This is on Version 12.4 (12D4e) of Xcode and
macOS Big Sur Version 11.2.3 (20D91)

Is there another warning option I have to disable to eliminate this warning?
C++ exit time destructor warning build option not working?
 
 
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