* libc/stdio/stdio.c (__swrite): declare "oldmode" only if it's
used later (ifdef __SCLE)
* libc/stdio/vfscanf.c (__svfscanf): declare "state" only if it's
used later (ifdef MB_CAPABLE)
* libc/string/memset.c (memset): removed unused variables "count"
and "unaligned_addr"
* libc/locale/locale.c (_setlocale_r): declare "lc_ctype" and
"last_lc_ctype" only of they're used later (ifdef MB_CAPABLE)
* libc/unix/getpwent.c (getpwnam): removed unused variables "uid"
and "gid"
(__sread): always read in binary mode
(__swrite): always write in binary mode
* libc/include/stdio.h: no getc/putc macros for cygwin; causes
compatibility issues with different dll versions
* libc/stdio/fopen.c: use __stextmode
* libc/stdio/fdopen.c: ditto
* libc/stdio/freopen.c: ditto
* libc/stdio/findfp.c: set up __SCLE for std{in,out,err}
* libc/stdio/local.h: declare __stextmode