Fix array underflow compiler warnings #226
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Given an array b[] of length n, pointers to &b[0]..&b[n] are defined (where only &b[0]..&b[n-1] can be validly dereferenced). &b[-1], or equivalently b-1, is not something we can use in valid Standard C. gcc 6 diagnoses this as: code/client/snd_wavelet.c:33:9: warning: array subscript is below array bounds [-Warray-bounds] and might take this undefined behaviour as permission to emit "more efficient" object code that is not what the author expected, for example nothing at all. Use a macro to fake a 1-based array instead.
This function is used in the Team Arena menus I don't think it's actually possible to reach this line with foundPlayerServerNames < 1, because by the time we get here we have set it to 1 + the actual number of servers; but if we did, it would clearly underflow into foundPlayerServerNames[-1], which would be undefined behaviour. gcc 6 diagnoses this with a warning: code/ui/ui_main.c: In function ‘UI_BuildFindPlayerList’: code/ui/ui_main.c:4138:16: warning: array subscript is below array bounds [-Warray-bounds] Also correct the sizeof() invocation to make it more obviously correct (in fact the buffers for names and addresses happen to both be of size MAX_ADDRESSLENGTH, so it was fine, but it's good to be obvious).
As with the other branch of the if/else, each element of foundPlayerServerNames is in fact the same size as each element of foundPlayerServerAddresses, so it was fine; but it's better to make it obvious that we are using the right array sizes.
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gcc 6 warns about some array underflows while compiling ioquake3. Please see the individual commit messages for more details.