[Bug bootstrap/40430] New: collect2.c fails to compile: new qualifiers in middle of multi-level non-const cast are unsafe

["ro at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>]

Between 20090522 (rev 147798) and 20090612 (rev 148427), collect2.c failed to
compile in stage2:

/vol/gccsrc/obj/gcc-4.5.0-20090612/6.5-gcc/./prev-gcc/xgcc
-B/vol/gccsrc/obj/gcc-4.5.0-20090612/6.5-gcc/./prev-gcc/
-B/vol/gcc/mips-sgi-irix6.5/bin/ -B/vol/gcc/mips-sgi-irix6.5/bin/
-B/vol/gcc/mips-sgi-irix6.5/lib/ -isystem /vol/gcc/mips-sgi-irix6.5/include
-isystem /vol/gcc/mips-sgi-irix6.5/sys-include     -g -O2 -DIN_GCC   -W -Wall
-Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wcast-qual
-Wold-style-definition -Wc++-compat -Wmissing-format-attribute -pedantic
-Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror -fno-common
 -DHAVE_CONFIG_H -I. -I. -I/vol/gcc/src/gcc-dist/gcc
-I/vol/gcc/src/gcc-dist/gcc/. -I/vol/gcc/src/gcc-dist/gcc/../include
-I/vol/gcc/src/gcc-dist/gcc/../libcpp/include -I/vol/gcc/include
-I/vol/gcc/include -I/vol/gcc/src/gcc-dist/gcc/../libdecnumber
-I/vol/gcc/src/gcc-dist/gcc/../libdecnumber/dpd -I../libdecnumber     \
        -DTARGET_MACHINE=\"mips-sgi-irix6.5\" \
        -c /vol/gcc/src/gcc-dist/gcc/collect2.c -o collect2.o 
cc1: warnings being treated as errors
/vol/gcc/src/gcc-dist/gcc/collect2.c: In function 'main':
/vol/gcc/src/gcc-dist/gcc/collect2.c:1170:8: error: new qualifiers in middle of
multi-level non-const cast are unsafe

I don't even understand what this message is supposed to mean.

It was probably introduced by this patch:

2009-06-01  Ian Lance Taylor  <iant@google.com>

        * attribs.c (register_attribute): Use CONST_CAST.
        * collect2.c (main): Use CONST_CAST2.
        (scan_prog_file): Likewise.
        * gcc.c (process_command, main): Likewise.
        * toplev.c (toplev_main): Likewise.

        * c-typeck.c (handle_warn_cast_qual): New static function,
        partially broken out of build_c_cast.
        (build_c_cast): Call handle_warn_cast_qual.
        * doc/invoke.texi (Warning Options): Document new effect of
        -Wcast-qual.


-- 
           Summary: collect2.c fails to compile: new qualifiers in middle of
                    multi-level non-const cast are unsafe
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ro at gcc dot gnu dot org
 GCC build triplet: mips-sgi-irix6.5
  GCC host triplet: mips-sgi-irix6.5
GCC target triplet: mips-sgi-irix6.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40430