[Patch] Fix filebuf_virtuals.cc for unsigned char platforms

[Kaveh R. Ghazi]

 > From: Mark Wielaard <mark@klomp.org>
 > 
 > Hi,
 > 
 > On Thu, 2003-02-06 at 23:36, Paolo Carlini wrote:
 > > Kaveh, Jeroen, Mark, could you possibly test the below on your
 > > favourite unsigned char platform and report?
 > 
 > On powerpc-unknown-linux-gnu without the patch compiling this test
 > gives:
 > 
 > /home/mark/src/gcc33/gcc/libstdc++-v3/testsuite/27_io/filebuf_virtuals.cc: In static member function `static bool MyTraits::eq(char, char)':
 > /home/mark/src/gcc33/gcc/libstdc++-v3/testsuite/27_io/filebuf_virtuals.cc:545: warning: comparison is always true due to limited range of data type
 > /home/mark/src/gcc33/gcc/libstdc++-v3/testsuite/27_io/filebuf_virtuals.cc:546: warning: comparison is always true due to limited range of data type
 > 
 > With the patch applied it compiles cleanly.
 > This was on the 3.3 branch and compiled by hand.

I applied the patch and ran "make -k check-target-libstdc++-v3" on
mips-sgi-irix6.5.  The failure went away.

		Thanks,
		--Kaveh
--
Kaveh R. Ghazi			ghazi@caip.rutgers.edu