>> -fexcess-precision=style >> This option allows further control over excess precision on >> machines where floating-point operations occur in a format >> with more precision or range than the IEEE standard and >> interchange floating-point types. By default, >> -fexcess-precision=fast is in effect; this means that >> operations may be carried out in a wider precision than the >> types specified in the source if that would result in faster >> code, and it is unpredictable when rounding to the types >> specified in the source code takes place. > > This sounds promising.
If I understand correctly, such compiler options are not promising. Even if LilyPond C++ source codes are compiled with such option, libguile without the option may calculate in a wider precision. In this case, the floating point calculation inside GUILE causes these issues.
