Contents|Index|Previous|Next  IBM RT options    The following ‘-m’ options are defined for the IBM RT PC. -min-line-mul Use an in-line code sequence for integer multiplies. This is the default.   -mcall-lib-mul Call lmul$$ for integer multiples.   -mfull-fp-blocks Generate full-size floating point data blocks, including the minimum amount of scratch space recommended by IBM. This is the default.   -mminimum-fp-blocks Do not include extra scratch space in floating point data blocks. This results in smaller code, but slower execution, since scratch space must be allocated dynamically.   -mfp-arg-in-fpregs Use a calling sequence incompatible with the IBM calling convention in which floating point arguments are passed in floating point registers.   Note: ‘varargs.h’ and ‘stdargs.h’ will not work with floating point operands if this option is specified. -mfp-arg-in-gregs Use the normal calling convention for floating point arguments. This is the default.   -mhc-struct-return Return structures of more than one word in memory, rather than in a register. This provides compatibility with the MetaWare HighC (hc) compiler. Use the option ‘-fpcc-struct-return’ for compatibility with the Portable C Compiler (pcc).   -mnohc-struct-return Return some structures of more than one word in registers, when convenient. This is the default. For compatibility with the IBM-supplied compilers, use the option ‘-fpcc-struct-return’ or the option ‘-mhc-struct-return’. Top|Contents|Index|Previous|Next