-qfloat=nans

The -qfloat=nans option causes the compiler to generate object code that detects the conversion of a single-precision signalling NaN (NaNS) to double precision. By default, the compiler generates object code that detects the use of a NaNS in all other situations required by the IEEE standard.

Very few programs actually require checks for NaNS. A NaNS cannot be produced by any floating-point operation, and must instead be explicitly created. A program only needs to be compiled with the -qfloat=nans option if it explicitly creates a signalling NaN.

Overview
-qfloat=nomaf
-qfloat=hssngl
-qfloat=hsflt
-qfloat=rndsngl
-qflttrap

Sample TRAP Exception Handler

float Compiler Option
flttrap Compiler Option