Re: m68k bootstrapping broken

[Bernardo Innocenti <bernie at develer dot com>]

Richard Zidlicky wrote:
> Hello,
>
> I am testing gcc-3.4-20031210. Bootstrapping fails with
> this problems:
>
> stage1/xgcc -Bstage1/ -B/usr/m68k-rz-linux/bin/ -c   -g -O2 -DIN_GCC   -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -pedantic -Wno-long-long -Wold-style-definition -Werror    -DHAVE_CONFIG_H    -I. -I. -I../../gcc-3.4-20031210/gcc -I../../gcc-3.4-20031210/gcc/. -I../../gcc-3.4-20031210/gcc/../include  \
>         ../../gcc-3.4-20031210/gcc/config/m68k/m68k.c -o m68k.o
> ../../gcc-3.4-20031210/gcc/config/m68k/m68k.c: In function `output_andsi3':
>
> ../../gcc-3.4-20031210/gcc/config/m68k/m68k.c:3285: warning: comparison between 
> signed and unsigned
> make[2]: *** [m68k.o] Error 1

Are you building with --enable-werror ?  This is a long-standing warning,
I'll fix that.

> /sources/rz-rpm/BUILD/build-gcc-3.4.0/gcc/xgcc -B/sources/rz-rpm/BUILD/build-gcc-3.4.0/gcc/ -B/usr/m68k-rz-linux/bin/ -B/usr/m68k-rz-linux/lib/ -isystem /usr/m68k-rz-linux/include -isystem /usr/m68k-rz-linux/sys-include -O2  -DIN_GCC    -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition  -isystem ./include -O3 -fomit-frame-pointer -m68020-60   -O2 -Dmc68060 -D__mc68060__ -g -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED  -I. -I -I../../gcc-3.4-20031210/gcc -I../../gcc-3.4-20031210/gcc/ -I../../gcc-3.4-20031210/gcc/../include   -DL_lshrdi3 -c ../../gcc-3.4-20031210/gcc/libgcc2.c -o libgcc/./_lshrdi3.o
>
> ../../gcc-3.4-20031210/gcc/libgcc2.c: In function `__lshrdi3':
> ../../gcc-3.4-20031210/gcc/libgcc2.c:361: error: unrecognizable insn:
> (insn 35 34 36 3 ../../gcc-3.4-20031210/gcc/libgcc2.c:350 (set (reg:SI 39)
>         (lshiftrt:SI (subreg:SI (reg/v:DI 35 [ uu ]) 0)
>             (reg:SI 38))) -1 (insn_list 34 (nil))
>     (expr_list:REG_DEAD (reg/v:DI 35 [ uu ])
>         (expr_list:REG_DEAD (reg:SI 38)
>             (expr_list:REG_EQUAL (lshiftrt:SI (subreg:SI (reg/v:DI 35 [ uu ]) 0)
>                     (reg:SI 38))
>                 (nil)))))
> ../../gcc-3.4-20031210/gcc/libgcc2.c:361: internal compiler error: in extract_insn, at recog.c:2061
>
> When I compile libgcc with the same flags with a crosscompiler this
> doesnt happen so it appears the compiler has miscompiled itself
> somewhere else.. anyone else seen this?

Never in m68k-*-uclinux nor m68k-*-elf.  Neither uses -m68020-60, but
I still can't reproduce the problem compiling the same code with m68k-uclinux-gcc:

% m68k-uclinux-gcc -O2  -DIN_GCC    -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition  -isystem ../../combined-HEAD/gcc -isystem ./include -O3 -fomit-frame-pointer -m68020-60   -O2 -Dmc68060 -D__mc68060__ -g -DHAVE_GTHR_DEFAULT -DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED  -I. -I -I../../combined-HEAD/gcc -I../../combined-HEAD/gcc/../include   -DL_lshrdi3 -c ../../combined-HEAD/gcc/libgcc2.c -o foo.o
% m68k-uclinux-objdump -d foo.o

foo.o:     file format elf32-m68k

Disassembly of section .text:

00000000 <__lshrdi3>:
  0:   48e7 3e00       moveml %d2-%d6,%sp@-
  4:   41ef 0018       lea %sp@(24),%a0
  8:   2410            movel %a0@,%d2
  a:   2628 0004       movel %a0@(4),%d3
  e:   2828 0008       movel %a0@(8),%d4
 12:   2002            movel %d2,%d0
 14:   2203            movel %d3,%d1
 16:   4a84            tstl %d4
 18:   672a            beqs 44 <__lshrdi3+0x44>
 1a:   7020            moveq #32,%d0
 1c:   9084            subl %d4,%d0
 1e:   4a80            tstl %d0
 20:   6f16            bles 38 <__lshrdi3+0x38>
 22:   2202            movel %d2,%d1
 24:   e1a9            lsll %d0,%d1
 26:   2a02            movel %d2,%d5
 28:   e8ad            lsrl %d4,%d5
 2a:   2003            movel %d3,%d0
 2c:   e8a8            lsrl %d4,%d0
 2e:   2c00            movel %d0,%d6
 30:   8c81            orl %d1,%d6
 32:   2005            movel %d5,%d0
 34:   2206            movel %d6,%d1
 36:   600c            bras 44 <__lshrdi3+0x44>
 38:   4285            clrl %d5
 3a:   4480            negl %d0
 3c:   2c02            movel %d2,%d6
 3e:   e0ae            lsrl %d0,%d6
 40:   2005            movel %d5,%d0
 42:   2206            movel %d6,%d1
 44:   4cdf 007c       moveml %sp@+,%d2-%d6
 48:   4e75            rts


Do you have any local patches that might be triggering this ICE?
You may also want to retry with a more recent CVS snapshot,
just in case.


> The crosscompiler so far works pretty well btw, working 2.4 & 2.6
> kernels and some 3.2 problems fixed.

That's good news.  As you might have noticed, the m68k backend has
been tortured quite a lot lately :-)

--
 // Bernardo Innocenti - Develer S.r.l., R&D dept.
\X/  http://www.develer.com/