Replace "alternative" boolean operator in conditional compilation directive

[mgroeber9110]

While looking over the warnings that MS VisualC produces, I noticed this oddity that looks like a typo in an #if directive, or at least something that is highly non-portable.

I don't have the LLVM compiler to test, but this just doesn't look right...

[slaren]

https://en.cppreference.com/w/cpp/language/operator_alternative

[mgroeber9110]

Thanks a lot for the reference! I was not aware of this part of the standard, and I think I have never seen that form being used anywhere before.

I noticed that it produces >100 warnings under Visual Studio 2022 (complaining about unexpected tokens at the end of a preprocessor directive).

Some more searching brought up this: https://stackoverflow.com/questions/24414124/why-does-vs-not-define-the-alternative-tokens-for-logical-operators - apparently Visual Studio supports this, but only by either including a header <iso646.h> or by adding the flag /permissive- to enforce greater standards compliance (in recent versions of VS).

As this is the only place in the project where this is used, my proposal would still be to change it to use the more common || form that is used everywhere else in the code, even if just for consistency and to make build output on Windows a bit less noisy.