c - Are pointers of the same size? -

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possible duplicates:
are there platforms pointers different types have different sizes?
are data pointers of same size in 1 platform?

sizeof(bucket *) same sizeof(int *),right?

btw,is char arr[]; valid in c90?

i believe there no requirement pointers same size. requirement object pointers can stored in void *, when cast void * , they'll same, , function pointers, if cast type of function pointer , again, same. (casting function pointers void * not guaranteed work. sorry if indicated otherwise.)

in practice, think time you'll find pointers of different sizes if care c++'s member-function pointers, or work on more obscure architecture.

in c90, char arr[]; valid way pre-declare global array of to-be-determined length. note char arr[] incomplete type, have declare before can use sizeof. it's not valid way in c99, make flexible array members.


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