LANG.TYPE.IARGT.TGMATH : Inappropriate Argument to <tgmath.h> Macro

Summary

A type-generic macro from <tgmath.h> is used with an operand argument of inappropriate essential type.

• All type-generic macros from <tgmath.h> will trigger a warning if used with an operand argument of essentially Boolean, essentially character, or essentially enum type.
• The following macros will also trigger a warning if used with an operand argument of essentially complex floating type: atan2, cbrt, ceil, copysign, erf, erfc, exp2, expm1, fdim, floor, fma, fmax, fmin, fmod, frexp, hypot, ilogb, ldexp, lgamma, llrint, llround, log10, log1p, log2, ogb, lrint, lround, nearbyint, nextafter, nexttoward , remainder, remquo, rint, round, scalbn, scalbln, tgamma, trunc.

This warning class utilizes the notion of essential type category as described in MISRA C:2012 Guidelines for the use of the C language in critical systems.

Properties

RETAIN_UNNORMALIZED_C_AST = Yes
WARNING_FILTER += allow class="Inappropriate Argument to <tgmath.h> Macro"

Example

#include <tgmath.h>

typedef enum {red, orange, yellow} color_t;

double call_sqrt(char ch, double d, int i, unsigned int u, color_t col){
    if ( ch<0 || d<0 || i<0 ){return -1;}
    double rv = 0;
    rv += sqrt(ch);  /* 'Inappropriate Argument to <tgmath.h> Macro' warning issued here
                      * - type is essentially character
                      */
    rv += sqrt(col); /* 'Inappropriate Argument to <tgmath.h> Macro' warning issued here
                      * - type is essentially enum
                      */
    rv += sqrt(i);                      /* ok: type is essentially signed */
    rv += sqrt(u);                      /* ok: type is essentially unsigned */
    rv += sqrt(d);                      /* ok: type is essentially real floating */
    return rv;
}

Relevant Configuration File Parameters

The following configuration file parameters affect checks for this warning class.

• REPORT_SIMILAR_WARNINGS
• RETAIN_UNNORMALIZED_C_AST
• WARNING_FILTER