Re: [PATCH] tabled: use LL to indicate 64-bit constant

[Jeff Garzik <jeff@garzik.org>]

[-- Attachment #1: Type: text/plain, Size: 859 bytes --]

On 01/12/2010 01:25 PM, Colin McCabe wrote:
> util.c: In function ‘objid_init’:
> util.c:331: warning: integer constant is too large for ‘long’ type
>
> with
>
> [cmccabe@stargazer tabled]$ gcc --version
> gcc (GCC) 4.4.1 20090725 (Red Hat 4.4.1-2)
>
> Now that I wrote a little test program, I can see that gcc handles the
> constant correctly. It still issues a warning for some reason.
> I guess gcc's C99 support is not perfect.

Is this on a 32-bit on 64-bit compiler platform?

Because Linux does

	#if __WORDSIZE == 64
	typedef unsigned long int       uint64_t;
	#else
	__extension__
	typedef unsigned long long int  uint64_t;
	#endif

which causes the comparison type (uint64_t objcount) to vary between 
32-bit and 64-bit platforms, even if the number of bits used to store it 
remains the same.

Strange...

	Jeff



[-- Attachment #2: x.c --]
[-- Type: text/plain, Size: 832 bytes --]

#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <stdint.h>

#if 1
#define X 0xff00000000000000
#else
#define X x
#endif

int main (int argc, char *argv[])
{
	uint32_t x = 0;

	if (__builtin_types_compatible_p (typeof (X), int))
		printf("type: int\n");
	else if (__builtin_types_compatible_p (typeof (X), unsigned int))
		printf("type: unsigned int\n");
	else if (__builtin_types_compatible_p (typeof (X), long))
		printf("type: long\n");
	else if (__builtin_types_compatible_p (typeof (X), unsigned long))
		printf("type: unsigned long\n");
	else if (__builtin_types_compatible_p (typeof (X), long long))
		printf("type: long long\n");
	else if (__builtin_types_compatible_p (typeof (X), unsigned long long))
		printf("type: unsigned long long\n");
	else
		printf("type: unknown\n");
	
	(void) x;

	return 0;
}