problem building library

[Vadim Egorov <egorovv at HotPOP dot com>]

Hello,

Building libstdc++ on Cygwin (gcc-2.95.1)I got following errors

make[2]: Entering directory `/home/build/libstdc++/src'
/bin/sh ../libtool --mode=compile c++ -DHAVE_CONFIG_H -I. -I/home/src/libstdc++/src -I.. -nostdinc++ -I/home/src/libstdc++ -I/home/src/libstdc++/stl -I/home/src/libstdc++/libio     -g -D_GNU_SOURCE -fno-implicit-templates -Wall -W -Wwrite-strings -Werror  -c /home/src/libstdc++/src/locale.cc
c++ -DHAVE_CONFIG_H -I. -I/home/src/libstdc++/src -I.. -nostdinc++ -I/home/src/libstdc++ -I/home/src/libstdc++/stl -I/home/src/libstdc++/libio -g -D_GNU_SOURCE -fno-implicit-templates -Wall -W -Wwrite-strings -Werror -c /home/src/libstdc++/src/locale.cc -o locale.o
cc1plus.exe: warnings being treated as errors
/home/src/libstdc++/src/locale.cc: In method `bool ctype<__wchar_t>::do_is(short unsigned int, __wchar_t) const':
/home/src/libstdc++/src/locale.cc:709: warning: comparison is always false due to limited range of data type
/home/src/libstdc++/src/locale.cc: In method `const __wchar_t * ctype<__wchar_t>::do_is(const __wchar_t *, const __wchar_t *, short unsigned int *) const':
/home/src/libstdc++/src/locale.cc:717: warning: comparison is always false due to limited range of data type
/home/src/libstdc++/src/locale.cc: In method `const __wchar_t * ctype<__wchar_t>::do_scan_not(short unsigned int, const __wchar_t *, const __wchar_t *) const':
/home/src/libstdc++/src/locale.cc:737: warning: comparison is always false due to limited range of data type
/home/src/libstdc++/src/locale.cc: In method `__wchar_t ctype<__wchar_t>::do_toupper(__wchar_t) const':
/home/src/libstdc++/src/locale.cc:745: warning: comparison is always false due to limited range of data type
/home/src/libstdc++/src/locale.cc: In method `const __wchar_t * ctype<__wchar_t>::do_toupper(__wchar_t *, const __wchar_t *) const':
/home/src/libstdc++/src/locale.cc:752: warning: comparison is always false due to limited range of data type
/home/src/libstdc++/src/locale.cc: In method `__wchar_t ctype<__wchar_t>::do_tolower(__wchar_t) const':
/home/src/libstdc++/src/locale.cc:760: warning: comparison is always false due to limited range of data type
/home/src/libstdc++/src/locale.cc: In method `const __wchar_t * ctype<__wchar_t>::do_tolower(__wchar_t *, const __wchar_t *) const':
/home/src/libstdc++/src/locale.cc:767: warning: comparison is always false due to limited range of data type
/home/src/libstdc++/src/locale.cc: In method `char ctype<__wchar_t>::do_narrow(__wchar_t, char) const':
/home/src/libstdc++/src/locale.cc:790: warning: comparison is always false due to limited range of data type
/home/src/libstdc++/src/locale.cc: In method `const __wchar_t * ctype<__wchar_t>::do_narrow(const __wchar_t *, const __wchar_t *, char, char *) const':
/home/src/libstdc++/src/locale.cc:798: warning: comparison is always false due to limited range of data type
make[2]: *** [locale.lo] Error 1
make[2]: Leaving directory `/home/build/libstdc++/src'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/build/libstdc++'
make: *** [all-recursive-am] Error 2

Compiler complains about code like:
  bool
  ctype<wchar_t>::do_is(mask __m, char_type __c) const
  {
    return (__c < _S_table_size) && (_S_table[__c] & __m); 
  }

where _S_table_size is 0 and __c unsigned.
Linux gcc-2.95.1 front end does not give this warning. 

Any idea ?

-- 
Regards,
Vadim Egorov