Re: [Chicken-users] Impossible constraint in asm

[Felix]

From: Lucas Jones <address@hidden>
Subject: [Chicken-users] Impossible constraint in asm
Date: Sun, 4 Jul 2010 23:17:02 +0100

> Hello,

Hi!

> 
> I am trying to compile a cross-chicken for the Wii using the latest
> DevKitPro. It provides a cross-compiling gcc 4.4.3 with the host
> 'powerpc-eabi'. (The compiler is called 'powerpc-eabi-gcc'.)
> 
> I call make like so:  make PLATFORM=linux PREFIX=$CHICKEN_PREFIX
> HOSTSYSTEM=powerpc-eabi DESTDIR=$CHICKEN_PREFIX/../ppc_chicken ARCH=
> install

Why do you use $CHICKEN_PREFIX here? CHICKEN_PREFIX is used at
runtime to override the installation prefix - is there a particular
reason why you set it in the Makefile? (I ask because it *might*
cause problems).

> 
> I also modified Makefile.linux to add '-I/usr/include' to the compiler
> options, as devKitPro doesn't provide all the necessary header files
> (e.g. systypes.h).
> 
> It compiles alright until it reaches 'tcp.c':
> 
> powerpc-eabi-gcc -fno-strict-aliasing -DHAVE_CHICKEN_CONFIG_H
> -I/usr/include -DC_ENABLE_PTABLES -I. -I./ \
>         -c -Os -fomit-frame-pointer \
>          \
>         -DC_BUILDING_LIBCHICKEN utils.c -o utils-static.o
> powerpc-eabi-gcc -fno-strict-aliasing -DHAVE_CHICKEN_CONFIG_H
> -I/usr/include -DC_ENABLE_PTABLES -I. -I./ \
>         -c -Os -fomit-frame-pointer \
>          \
>         -DC_BUILDING_LIBCHICKEN tcp.c -o tcp-static.o
> tcp.c: In function 'f_2263':
> tcp.c:176: error: impossible constraint in 'asm'
> make[2]: *** [tcp-static.o] Error 1
> 
> I've read that this error is sometimes caused by a change in GCC;
> should I try downgrading to an older GCC?

I can't say for sure, but since you include system C headers (are you
building on an x86 system?), I wouldn't be surprised if these get in
the way somehow. I would at least try to use the same gcc version
as you use on your development machine. If that doesn't help, could
you show me the relevant lines from tcp.c that trigger the error?


cheers,
felix