| I get weird error messages where I don't see errors.

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Q:

The compiler sometimes report strange error messages on places where I really can not see any errors. For example, the compiler reports the error

    parse error before 'void'

but the statement on which the error is reported was

    int cexp;

I am really confused. First, I don't see any errors here, and second, I can't see any 'void' keywords here!

A:

Yes, such problems may really be the source of big frustrations. There is nothing wrong with above statement, but note that `'cexp'` is a function defined in timath.h header file, and you can not use this name as a name of a variable. Now you can say why you got such strange error message? See, the most of functions in TIGCCLIB are translated by the preprocessor into constructions which perform indirect function calls through a TIOS jump table. In other words, `'cexp'` will be replaced by the preprocessor into the indirect function call constructor whenever it is used. So, the innocent statement like

    int cexp;

will be converted into

    int (*(void(**)(float,float,float*,float*))(*(long*)0xC8+1316));

which is a syntax error. And the error is just before `'void'`.
I can not do anything against such hidden errors. Whenever you encounter strange errors without obvious reasons, check whether you used reserved library name for your identifier. The chance of making such errors is much smaller if you include only the necessary header files than if you include the general header file tigcclib.h.