MISRA.INCL.TGMATH.2012

MISRA C 2012 Rule 21.11: The standard header file <tgmath.h> shall not be used

Category: Required

Analysis: Decidable, Single Translation Unit

Applies to: C99

Amplification

None of the facilities that are specified as being provided by <tgmath.h> shall be used.

Rationale

Using the facilities of <tgmath.h> may result in undefined behaviour.

Limitation

On Windows (Visual Studio), it is possible to compile without including tgmath.h but using its facilities - Windows assumes that the <tgmath> file is missing and includes it anyway. This is a known limitation; the checker won't report on calling functions from these headers in this case as tgmath has methods from math.h and complex.h headers.

Example

#include <tgmath.h>        /* Non-compliant    */

float f1, f2;

void f ( void )
{
    f1 = sqrt ( f2 );        /* Non-compliant - generic sqrt used    */
}

#include <math.h>

float f1, f2;

void f ( void )
{
    f1 = sqrtf ( f2 );        /* Compliant - float version of sqrt used    */
}