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All expression statements, such as function calls with an ignored value, are implicitly cast to void. Since a return value often contains important information about possible errors it should always be checked, otherwise the cast should be made explicit to signify programmer intent. If a function returns no meaningful value it should be declared with return type void.
This is a general recommendation encompassing encompasses MEM32-C. Detect and handle memory allocation errors, FIO04-A. Detect and handle input and output errors and FIO34-C. Use int to capture the return value of character IO functions.
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