bug in lrint [was: FW: Printing long int in C program under cygwin64]

Brian Inglis Brian.Inglis@SystematicSw.ab.ca
Thu May 25 17:34:00 GMT 2017


On 2017-05-24 19:31, Steven Penny wrote:
> On Wed, 24 May 2017 16:36:03, Steven Penny wrote:
>> Aren’t both wrong? By definition %i is a signed integer, and size_t is
>> unsigned.
>> So %zu or %llu would be more correct:
>> http://wikipedia.org/wiki/C_data_types
>> They all seem to do the job though:
> Correcting myself. Here is why you cannot use %zi:
>	$ cat alfa.c
>	#define __USE_MINGW_ANSI_STDIO 1
>	#include <stdio.h>
>	int main() {
>		printf("%zi %zu %llu\n", __SIZE_MAX__, __SIZE_MAX__, __SIZE_MAX__);
>	}
>	$ x86_64-w64-mingw32-gcc -o alfa alfa.c
>	$ ./alfa
>	-1 18446744073709551615 18446744073709551615

I think either 10+ digits or a negative value are adequate indicators
that something may have gone wrong, and -1 is a more compact format for
*_MAX, unless you need to see actual values.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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