the casts of the argument to unsigned int suppressed diagnosis of
errors like passing a pointer instead of a character. putting the
actual function call in an unreachable branch restores any diagnostics
that would be present if the macros didn't exist and functions were
used.
the old behavior of exposing nothing except plain ISO C can be
obtained by defining __STRICT_ANSI__ or using a compiler option (such
as -std=c99) that predefines it. the new default featureset is POSIX
with XSI plus _BSD_SOURCE. any explicit feature test macros will
inhibit the default.
installation docs have also been updated to reflect this change.
issue reported by nsz, but it's actually not just pedantic. the
functions can take input of any arithmetic type, including floating
point, and the behavior needs to be as if the conversion implicit in
the function call took place.