[Bug bootstrap/54863] New: [4.8 regresssion] multiple 'comparison between signed and unsigned integer expressions' errors in simplify-rtx.c:simplify_truncation broke m68k-linux bootstrap

["mikpe at it dot uu.se" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54863

             Bug #: 54863
           Summary: [4.8 regresssion] multiple 'comparison between signed
                    and unsigned integer expressions' errors in
                    simplify-rtx.c:simplify_truncation broke m68k-linux
                    bootstrap
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: mikpe@it.uu.se


Attempting to bootstrap gcc-4.8-20121007 on m68k-linux failed with:

/mnt/scratch/objdir48/./prev-gcc/g++ -B/mnt/scratch/objdir48/./prev-gcc/
-B/mnt/scratch/install48/m68k-unknown-linux-gnu/bin/ -nostdinc++
-B/mnt/scratch/objdir48/prev-m68k-unknown-linux-gnu/libstdc++-v3/src/.libs
-B/mnt/scratch/objdir48/prev-m68k-unknown-linux-gnu/libstdc++-v3/libsupc++/.libs
-I/mnt/scratch/objdir48/prev-m68k-unknown-linux-gnu/libstdc++-v3/include/m68k-unknown-linux-gnu
-I/mnt/scratch/objdir48/prev-m68k-unknown-linux-gnu/libstdc++-v3/include
-I/mnt/scratch/gcc-4.8-20121007/libstdc++-v3/libsupc++
-L/mnt/scratch/objdir48/prev-m68k-unknown-linux-gnu/libstdc++-v3/src/.libs
-L/mnt/scratch/objdir48/prev-m68k-unknown-linux-gnu/libstdc++-v3/libsupc++/.libs
-c   -g -O2 -gtoggle -DIN_GCC   -fno-exceptions -fno-rtti
-fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings
-Wcast-qual -Wmissing-format-attribute -pedantic -Wno-long-long
-Wno-variadic-macros -Wno-overlength-strings -Werror   -DHAVE_CONFIG_H -I. -I.
-I/mnt/scratch/gcc-4.8-20121007/gcc -I/mnt/scratch/gcc-4.8-20121007/gcc/.
-I/mnt/scratch/gcc-4.8-20121007/gcc/../include
-I/mnt/scratch/gcc-4.8-20121007/gcc/../libcpp/include 
-I/mnt/scratch/gcc-4.8-20121007/gcc/../libdecnumber
-I/mnt/scratch/gcc-4.8-20121007/gcc/../libdecnumber/dpd -I../libdecnumber
-I/mnt/scratch/gcc-4.8-20121007/gcc/../libbacktrace   
/mnt/scratch/gcc-4.8-20121007/gcc/simplify-rtx.c -o simplify-rtx.o
/mnt/scratch/gcc-4.8-20121007/gcc/simplify-rtx.c: In function 'rtx_def*
simplify_truncation(machine_mode, rtx, machine_mode)':
/mnt/scratch/gcc-4.8-20121007/gcc/simplify-rtx.c:671:34: error: comparison
between signed and unsigned integer expressions [-Werror=sign-compare]
       && INTVAL (XEXP (op, 1)) < precision)
                                  ^
/mnt/scratch/gcc-4.8-20121007/gcc/simplify-rtx.c:683:34: error: comparison
between signed and unsigned integer expressions [-Werror=sign-compare]
       && INTVAL (XEXP (op, 1)) < precision)
                                  ^
/mnt/scratch/gcc-4.8-20121007/gcc/simplify-rtx.c:695:34: error: comparison
between signed and unsigned integer expressions [-Werror=sign-compare]
       && INTVAL (XEXP (op, 1)) < precision)
                                  ^
/mnt/scratch/gcc-4.8-20121007/gcc/simplify-rtx.c:709:34: error: comparison
between signed and unsigned integer expressions [-Werror=sign-compare]
       && INTVAL (XEXP (op, 1)) < op_precision)
                                  ^
cc1plus: all warnings being treated as errors
make[3]: *** [simplify-rtx.o] Error 1
make[3]: Leaving directory `/mnt/scratch/objdir48/gcc'
make[2]: *** [all-stage2-gcc] Error 2
make[2]: Leaving directory `/mnt/scratch/objdir48'
make[1]: *** [stage2-bubble] Error 2
make[1]: Leaving directory `/mnt/scratch/objdir48'
make: *** [bootstrap] Error 2

The previous weekly snapshot, 4.8-20120930, bootstrapped fine.

Complete configuration parameters:
/mnt/scratch/gcc-4.8-20121007/configure --prefix=/mnt/scratch/install48
--enable-bootstrap --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-languages=c,c++ --disable-dssi
--with-java-home=/usr/lib/jvm/java-1.5.0-gcj-1.5.0.0/jre
--enable-libgcj-multifile --disable-java-maintainer-mode
--with-ecj-jar=/usr/share/java/eclipse-ecj.jar --disable-libjava-multilib
--disable-sjlj-exceptions --disable-libmudflap --disable-plugin --disable-lto
--disable-multilib