[Bug middle-end/25905] New: [4.2 regression] ICE in expand_compound_operation

["schwab at suse dot de" <gcc-bugzilla@gcc.gnu.org>]

$ ./xgcc -B./ unwind-dw2-fde-glibc.i -S -O -v
Reading specs from ./specs
Target: m68k-linux
Configured with: ../gcc/configure --prefix=/usr/local/m68k-linux
--host=powerpc-linux --target=m68k-linux
--with-sysroot=/usr/local/m68k-linux/m68k-linux/sys-root --enable-shared
--enable-__cxa_atexit --with-system-zlib
--enable-languages=c,c++,fortran,java,objc --no-create --no-recursion
Thread model: posix
gcc version 4.2.0 20060121 (experimental)
 ./cc1 -fpreprocessed unwind-dw2-fde-glibc.i -quiet -dumpbase
unwind-dw2-fde-glibc.i -auxbase unwind-dw2-fde-glibc -O -version -o
unwind-dw2-fde-glibc.s
GNU C version 4.2.0 20060121 (experimental) (m68k-linux)
        compiled by GNU C version 4.0.2 20050901 (prerelease) (SUSE Linux).
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: 0ad6bd3654ebd3f56f26d23ad96d1796
../../gcc/gcc/unwind-dw2-fde.c: In function
‘fde_single_encoding_compare’:
../../gcc/gcc/unwind-dw2-fde.c:350: internal compiler error: in
expand_compound_operation, at combine.c:5644

Caused by:

r109961 | bonzini | 2006-01-19 15:54:57 +0100 (Do, 19 Jan 2006) | 13 lines

2006-01-19  Paolo Bonzini  <bonzini@gnu.org>

        * combine.c (try_combine): Do not worry about MEMs wrapped by USEs.
        (expand_compound_operation, expand_field_assignment): Fail if the
        bit lengths of an extract operation are out of range.
        (make_extraction): Compute wanted_inner_mode based on the position
        and length of the extraction.  Make it extraction_mode for non-constant
        positions, and do not modify offset in that case.  When generating a
        new MEM, use a mode that can hold the extraction while keeping correct
        alignment.  Remove code that supported MEMs wrapped by USEs.
        (simplify_shift_const_1, force_to_mode) <case USE>: Remove.


-- 
           Summary: [4.2 regression] ICE in expand_compound_operation
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: schwab at suse dot de
GCC target triplet: m68k-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25905