[Bug libffi/46792] New: libffi fails building for cris-elf

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46792

           Summary: libffi fails building for cris-elf
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libffi
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: hp@gcc.gnu.org
            Target: cris-axis-elf


When support for CRIS v32 was added to the CRIS port, a "v32" multilib was
added to cris-elf.  Unfortunately, libffi wasn't updated, resulting in build
failure for the whole of gcc without special configure options:

libtool: compile:  /tmp/hpautotest-gcc1/cris-elf/gccobj/./gcc/xgcc
-B/tmp/hpautotest-gcc1/cris-elf/gccobj/./gcc/ -nostd\
inc -B/tmp/hpautotest-gcc1/cris-elf/gccobj/cris-elf/v32/newlib/ -isystem
/tmp/hpautotest-gcc1/cris-elf/gccobj/cris-elf/\
v32/newlib/targ-include -isystem /tmp/hpautotest-gcc1/gcc/newlib/libc/include
-B/tmp/hpautotest-gcc1/cris-elf/gccobj/cr\
is-elf/v32/libgloss/cris
-L/tmp/hpautotest-gcc1/cris-elf/gccobj/cris-elf/v32/libgloss/libnosys
-L/tmp/hpautotest-gcc1/g\
cc/libgloss/cris -B/tmp/hpautotest-gcc1/cris-elf/pre/cris-elf/bin/
-B/tmp/hpautotest-gcc1/cris-elf/pre/cris-elf/lib/ -i\
system /tmp/hpautotest-gcc1/cris-elf/pre/cris-elf/include -isystem
/tmp/hpautotest-gcc1/cris-elf/pre/cris-elf/sys-inclu\
de -march=v32 -mbest-lib-options -DHAVE_CONFIG_H -I.
-I/tmp/hpautotest-gcc1/gcc/libffi -I. -I/tmp/hpautotest-gcc1/gcc/l\
ibffi/include -Iinclude -I/tmp/hpautotest-gcc1/gcc/libffi/src -I.
-I/tmp/hpautotest-gcc1/gcc/libffi/include -Iinclude -\
I/tmp/hpautotest-gcc1/gcc/libffi/src -g -O2 -MT src/cris/sysv.lo -MD -MP -MF
src/cris/.deps/sysv.Tpo -c /tmp/hpautotest\
-gcc1/gcc/libffi/src/cris/sysv.S -o src/cris/sysv.o
/tmp/hpautotest-gcc1/gcc/libffi/src/cris/sysv.S: Assembler messages:
/tmp/hpautotest-gcc1/gcc/libffi/src/cris/sysv.S:51: Error: Unknown opcode:
`push'

A temporary fix is to disable libffi for cris-elf. (No other action should be
necessary: cris-linux doesn't have a v32 multilib and the crisv32-* tuples
aren't matched by libffi configure.)
The correct fix is not that hard; there's a common assembly-language subset
used in other assembly codes, for example newlib+libgloss.
E.g. push R -> subq 4,$sp / move.d R,[$sp]
(equivalent in function, size and cycles except when condition codes need to be
preserved.)
I'll fix this the temporary way, then suspend the PR.