* libc/stdio/open_memstream.c (internal_open_memstream_r): Fix max
buffer size to be in wchar_t units if wide == 1 is passed in. In
this case, also initialize the first character of the buffer to be
wide char null.
(_open_wmemstream_r): Cast buf to be (char **) to avoid warning.
* libc/stdlib/mbtowc_r.c (_mbtowc_r): Change all occurences of
incrementing the size_t value n to first check that n is not already
size_t -1. Fix some compiler warnings.
* libc/stdlib/wcstod.c: Add includes for <wctype.h> and <math.h>.