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A very common idiom is "T p = malloc(n sizeof *p)". That only works if sizeof doesn't evaluate its arguments.
by gandalf013 9y ago
A very common idiom is "T p = malloc(n sizeof *p)". That only works if sizeof doesn't evaluate its arguments.
- kazinator 9y agoWhy not? Suppose you have a C99 VLA object, and you want to malloc the equivalent amount of space. Couldn't you just do this: int vla[nparam]; int *pcopyspace = malloc(sizeof vla); Here sizeof vla is basically just nparam sizeof(int). vla* is evaluated to the extent of calculating its run-time size.