[CMake] TRY_RUN wrong program return value with --debug-compile

[Hendrik Sattler]

Zitat von Eduardo Alberto Hernández Muñoz <coz.eduardo.hernandez at gmail.com>:
> I have the file check_openal_spec_version_1_1.cpp which contains:
>
>     #define AL_VERSION_1_1
>     #define AL_VERSION_1_0
>
>     int main()  {
>
>     #ifdef AL_VERSION_1_1
>         return 2;
>     #elif AL_VERSION_1_0
>         return 1;
>     #else
>         return -1;
>     #endif
>
>     }

That elif is wrong if you don't assign a value to the define.

> The interesting part, is that this problem only happens when I pass
> the --debug-trycompile to cmake. Without the flag, CMake works
> wonderfully.

That option is known to cause such problems, don't know why.

HS