Does `sizeof(void)` tell us the size of the void type in C or C ?

Size of the Elusive void

Question:

Can we determine the size of the void type in C or C ? Consider the following code:

void *p = malloc(sizeof(void));

Extension: If sizeof(void) returns 1 in GCC, will the pointer p increment to 0x2346 after p if p initially held 0x2345?

Answer:

The void type fundamentally lacks size, rendering the expression sizeof(void) meaningless and leading to a compilation error. In C , it is strictly prohibited.

Unexpected Discovery:

Surprisingly, when compiling in GNU C, sizeof(void) yields 1. However, this behavior is limited to GNU C and not observed in C or other implementations.

Implications:

Despite the unexpected return value in GNU C, it's crucial to note that void remains a type without size. Pointers to void, such as p in the example, are genuine pointers and can be incremented like any other pointer. The increment operation in the extension question will behave as expected, with p pointing to the next available memory address.

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