Обсуждение: MSVC compilers complain about snprintf

The MSVC compilers are whingeing about recent changes in snprintf.c:


    src\port\snprintf.c(1051): warning C4146: unary minus operator
    applied to unsigned type, result still unsigned


The line in question reads:

    uvalue = -(unsigned long long) value;

cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Hi,

On 2018-10-17 17:27:14 -0400, Andrew Dunstan wrote:
> 
> The MSVC compilers are whingeing about recent changes in snprintf.c:
> 
> 
>    src\port\snprintf.c(1051): warning C4146: unary minus operator
>    applied to unsigned type, result still unsigned
> 
> 
> The line in question reads:
> 
>    uvalue = -(unsigned long long) value;

Yea, that's intended. Is there a way to silence that one, but just keep
the code largely similar?

Greetings,

Andres Freund

On 10/17/2018 05:31 PM, Andres Freund wrote:
> Hi,
>
> On 2018-10-17 17:27:14 -0400, Andrew Dunstan wrote:
>> The MSVC compilers are whingeing about recent changes in snprintf.c:
>>
>>
>>     src\port\snprintf.c(1051): warning C4146: unary minus operator
>>     applied to unsigned type, result still unsigned
>>
>>
>> The line in question reads:
>>
>>     uvalue = -(unsigned long long) value;
> Yea, that's intended. Is there a way to silence that one, but just keep
> the code largely similar?


Probably something like:

    #if (_MSC_VER >= 1800)
    #pragma warning(disable:4146)
    #endif


based on float.h.



cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Andrew Dunstan <andrew.dunstan@2ndquadrant.com> writes:
> The MSVC compilers are whingeing about recent changes in snprintf.c:
>     src\port\snprintf.c(1051): warning C4146: unary minus operator
>     applied to unsigned type, result still unsigned

Yeah, see commit 4868e4468590bc32f9c3afed4ec795d6a7732c9d.

The law of conservation of warning messages seems to be at work :-(

            regards, tom lane