A preprocessor "trick" not mentioned in the article is the use of GNU statement expressions. The article describes the do {} while(0) trick to make macros look

A preprocessor "trick" not mentioned in the article is the use of GNU statement expressions. The article describes the do {} while(0) trick to make macros look like statements. They can then basically be used like inline void function calls. But what if you want to write a macro to replace an inline function that returns a result? Statement expressions [1] solve that problem. Now you can finally do this: int _foo(int x) { return 2 * x; } #ifdef __DEBUG__ # define foo(x) \({ \ int r = _foo(x); \ printf( \ "foo returned: %d (%s:%d)\n", \ r, __FILE__, __LINE__ \ ); \ r; \ }) #else # define foo _foo #endif They are supported by most popular compilers which are not made by Microsoft (including GCC and clang). [1] https://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html https://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html