Half-precision floating-point numbers are provided by:
If a VFP coprocessor is not available, or if a VFPv3 coprocessor is used that does not have
the extension, half-precision floating-point numbers are supported through the
Half-precision floating-point numbers can only be used when selected with the
fp16_format= compiler command-line
The C++ name mangling for the half-precision data type is specified in the C++ generic Application Binary Interface (ABI).