Stupid C++ Tricks: do/while(0) and C4127
March 1, 2009
A nice little quickie: I briefly discuss in my assert ramblings why it’s important to wrap all of your multi-line macros in do/while(0) blocks. An unfortunate side-effect of this is that the construction
// NOISY CODE
#define MULTI_LINE_MACRO \
do { \
std::printf(“Hello “); \
std::printf(“world!\n”); \
} while (0)
will trigger C4127: “Conditional expression is constant” in Visual Studio 2003/2005, and [...]
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