Re: My idea of fully-portable C code

In message <bf1f13dd-5bb1-4da7-b339-dbfc46944cca@xxxxxxxxxxxxxxxxxxxxxxxxxxx>, Tomás Ó hÉilidhe <toe@xxxxxxxxxxx> writes
On May 13, 7:59 pm, Hans-Bernhard Bröker <HBBroe...@xxxxxxxxxxx>
wrote:
> #define TOTAL_BITS_NEEDED (QUANTITY_CHUNKS * BITS_PER_CHUNK)

Bad macro.  Parentheses missing around QUANTITY_CHUNKS and
BITS_PER_CHUNK leave the code vulnerable to funny definitions of those
constants (e.g. #define BITS_PER_CHUNK 2+3)  The same problem occurs
repeatedly later on.


You're confusing things. A macro is a self-contained, self-sufficient
entity. If I have a macro called QUANTITY_CHUNKS, then it should be
able to be used on its own without parentheses. If it needs
parentheses, then it is ill-formed.


Now you are running counter to most standards and guides for portability and safety.


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