Re: Hellp with type promotion

manochavishal@xxxxxxxxx wrote:

int main(void)
{
char c = 'C';
test(c);

return 0;
}

void test(char c)
{
printf("Size of char is %d",sizeof(c));

}

1. This code is not legal. You don't have a declaration for test, and
the definition is different than the default declaration you would get
with a pre-C99 compiler. Also, printf() is a variadic function a
requires a prototype. The best way is to include <stdio.h>

2. Even if there were a legal implicit declaration or an old-style
declaration, that wouldn't matter. Except for variable-length arrays,
sizeof is performed at compile time. What the arguments get promoted to
at run-time have no bearing on what's printed there. It will be
sizeof(char), which is guaranteed to be 1, always.



Brian
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