Re: [Qemu-devel] Build errors

[James Boddington]

Thomas Schwinge wrote:
> Hello!
>
> Yesterday, I tried to build the latest CVS version of QEMU, but failed:
>
> CFLAGS set to '-Os -pipe -march=athlon-xp'
> #v+
> gcc -I/package/misc/spf/qemu-20041024T153139Z-1/spf/sdl/include 
> -I/package/misc/spf/qemu-20041024T153139Z-1/spf/zlib/include -O2 
> -fno-strict-aliasing -Os -pipe -march=athlon-xp -fomit-frame-pointer -I. 
> -I/tmp/build/qemu/qemu-20041024T153139Z/target-i386 
> -I/tmp/build/qemu/qemu-20041024T153139Z -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 
> -D_LARGEFILE_SOURCE -I/tmp/build/qemu/qemu-20041024T153139Z/slirp -c -o 
> helper2.o /tmp/build/qemu/qemu-20041024T153139Z/target-i386/helper2.c
> /tmp/build/qemu/qemu-20041024T153139Z/softmmu_template.h: In function 
> `__stq_mmu':
> /tmp/build/qemu/qemu-20041024T153139Z/softmmu_template.h:223: error: unable to 
> find a register to spill in class `GENERAL_REGS'
> /tmp/build/qemu/qemu-20041024T153139Z/softmmu_template.h:223: error: this is 
> the insn:
> (insn:HI 306 426 307 13 (parallel [
>             (set (reg:DI 0 ax [176])
>                 (lshiftrt:DI (reg/v:DI 59 [ val ])
>                     (subreg:QI (reg:SI 185) 0)))
>             (clobber (scratch:SI))
>             (clobber (reg:CC 17 flags))
>         ]) 306 {lshrdi3_1} (nil)
>     (expr_list:REG_UNUSED (reg:CC 17 flags)
>         (expr_list:REG_UNUSED (scratch:SI)
>             (nil))))
> /tmp/build/qemu/qemu-20041024T153139Z/softmmu_template.h:223: confused by 
> earlier errors, bailing out
> make[1]: *** [helper.o] Error 1
> make[1]: *** Waiting for unfinished jobs....
> make[1]: Leaving directory 
> `/fs/data/mount/tmp/build/qemu/qemu-20041024T153139Z/i386-softmmu'
> make: *** [all] Error 1

I get the same error when I try -march=athlon-xp with gcc 3.4.2 and a 
simillar error when I try the same CFLAGS with gcc 3.3.5.

I am wondering if this a bug in qemu or is qemu triggering a bug in gcc? 
Searching http://gcc.gnu.org/bugzilla/ for "unable to find a register to 
spill in class" does show some gcc related errors.

The highest march I can use without getting a compile error is 
-march=pentium. I am not having any problems using mtune or mcpu.

I just compiled qemu with

make CFLAGS="-O2 -mtune=athlon-xp -fomit-frame-pointer"

using gcc 3.4.2. It installed ok and runs the linux image I have been 
playing with.

--
   James