The Windows printf family handed %a and %A to the host, whose UCRT prints
a subnormal unnormalised (0x0.0000000000001p-1022) and pads with zeros
even when the - flag is given (%-010a of 1.5 gave 0x001.8p+0). The
libc.prx that titles ship normalises subnormals (0x1p-1074), rounds a
shorter precision half up without renormalising a carry, and lets -
override 0, as C requires.
Finite doubles are now formatted here, checked against three titles'
copies of libc.prx run side by side.
Co-Authored-By: Claude Opus 5.5 <[email protected]>