Re: 0xdeadbeef vs 0xdeadbeefL

[tom st denis]

--- David Eger <eger@xxxxxxxxxxxxx> wrote:
> Is there a reason to add the 'L' to such a 32-bit constant like this?
> There doesn't seem a great rhyme to it in the headers...

IIRC it should have the L [probably UL instead] since numerical
constants are of type ``int'' by default.  

Normally this isn't a problem since int == long on most platforms that
run Linux.  However, by the standard 0xdeadbeef is not a valid unsigned
long constant.

Consider the following...

#include <stdio.h>
int main(void)
{
  unsigned int x;
  x = 4;
  if (x < 0xdeadbeef) printf("hello");
  return 0;
}

If you run splint on that you get 

---
Splint 3.1.1 --- 13 Jun 2004

test2.c: (in function main)
test2.c:7:7: Operands of < have incompatible types (unsigned int, int):
                x < 0xdeadbeef
  To ignore signs in type comparisons use +ignoresigns

Finished checking --- 1 code warning
---

As far as I know splint follows C99 which means that it thinks the
constant is "int".  

Tom


	
		
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