Input charsets - What's going on?

[Paolo Bonzini]

cppcharset.c's _cpp_default_encoding use nl_langinfo (CHARSET) to find 
the default input charset.  This usage is guarded by a configure script 
symbol, HAVE_LANGINFO_CODESET.  Too bad, in the current GCC sources, 
HAVE_LANGINFO_CODESET is never defined and is not even in the 
auto-host.h template.  This means that GCC never attempts any input 
charset conversion except if -finput-charset is given.

While moving libcpp to the toplevel, I put the test correctly in the 
libcpp configure script so that nl_langinfo (CODESET) is now used to 
find out the default input charset.  Problem is, this fails miserably. 
fold-const.c and java/typeck.c had two non-breaking spaces (Unicode 160) 
which I have already committed fixes for, and libgfortran's files have 
Tobi's name in it which sports an umlaut-u character (Unicode 252): both 
of these break the default codeset on my machine, which is 
ANSI_X3.4-1968, and cause the bootstrap to error because a conversion 
failure.

Is the feature broken by design?  How should I proceed in the standalone 
libcpp?

Paolo