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I know in C return type of sizeof operator is size_t being unsigned integer type defined in <stdint.h>. Which means max size of it should be 65535 as stated in C99 standard 7.18.3:
limit of size_t
SIZE_MAX 65535
However in gcc-4.8.2 header file stdint.h has defined its size much greater than 65535 contradicting to which is stated in C99 standard as below shown,
/* Limit of `size_t' type. */
# if __WORDSIZE == 64
# define SIZE_MAX (18446744073709551615UL)
# else
# define SIZE_MAX (4294967295U)
# endif
Kindly help me in understanding why there is a difference or reason behind my misinterpretation.
333
On a typical 64-bit system, the size_t will be 64-bit, but unsigned int will be 32 bit. So we cannot use them interchangeably. One standard recommendation is that the size_t be at most as big as an unsigned long.
No; size_t is not necessarily whatever you mean by 'the word size' of the machine that will run the code (in the case of cross-compilation) or that compiled the code (in the normal case where the code will run on the same type of machine that compiled the code).
The standard says that SIZE_MAX must be at least 65535.
It specifies no upper bound, and gcc's implementation is perfectly valid.
Quoting the reference you cited (emphasis added):
Its implementation-defined value shall be equal to or greater in magnitude (absolute value) than the corresponding value given below, with the same sign.
174
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