8.7.1 Implementation Defined Options

format and range of floating point numbers:

The double type of C, which is IEEE DP FP (binary64) on most platforms (exception: ARM with soft floats).

results of REPRESENT when float is out of range:

Represent produces results for all inputs. For infinities, it produces as much of “infinity” or “-infinity” as fits in the buffer. For NaNs, it produces as much of “NaN” as fits in the buffer. The remaining buffer is filled with spaces. For infinities and NaNs, flag2 (valid) is false, otherwise true.

rounding or truncation of floating-point numbers:

IEEE-FP-based (i.e., most) systems by default round to nearest, and break ties by rounding to even (i.e., such that the last bit of the mantissa is 0).

size of floating-point stack:

s" FLOATING-STACK" environment? drop . gives the total size of the floating-point stack (in floats). You can specify this on startup with the command-line option -f (see Invoking Gforth).

width of floating-point stack:

1 floats.