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Preprocessor: predefined macros

__cplusplus

In order to describe the wchar_t datatype, there is WCHAR_MAX (and further macros such as __WCHAR_MAX__ and __WCHAR_TYPE__ in gcc).

Print predefined macros on the command line

With the GNU compiler's command line option -dM, it's possible to quickly show the values of predefined macros..

For example, in PowerShell like so:

write-output '' | g++ -dM -E -x c++  -