When configuring a s390->s390 or cris->cris crosscompiler

(ok, I haven't hit this yet, but one of these days I'll get me an account

on an s390, and then I'll need this patch :-), you'll get the

following error:

+ /build/s390-unknown-linux-gnu/gcc-3.3-glibc-2.3.2/gcc-3.3/configure

--target=s390-unknown-linux-gnu --host=s390-host_unknown-linux-gnu

--prefix=/result/s390-unknown-linux-gnu/gcc-3.3-glibc-2.3.2

--enable-languages=c

--with-local-prefix=/result/s390-unknown-linux-gnu/gcc-3.3-glibc-2.3.2/s390-

unknown-linux-gnu --enable-threads=no --without-headers --with-newlib

--disable-shared

...

*** --with-headers is only supported when cross compiling

This error pops up only when you're using Daniel Jacobowitz's technique

of slightly changing the target and host tuples to make them different

enough to force gcc's build system to not try to pull in system libraries

or headers.  This technique is needed e.g. to build an x86 -> x86

cross-compiler.

(The LFS developers ran into the same bug that prompted me to use

this technique; they point people who run into it to

http://linuxfromscratch.org/~greg/pure_lfs.txt, which is a different

way of avoiding this problem.  I think the tuple tweak is the way to go, though.)

config-patches@gnu.org rejected this patch, on the grounds that there

is only one vendor of each of those two architectures, so the 

canonicalization is by definition correct.  When I pointed out the

difficulty this causes for people building s390 -> s390 or

cris -> cris compilers that are incompatible with the system

libraries and thus must be built like cross-compilers, he grumped and said 

"autoconf should let you specify a cross-compiler in some other way than

comparing tuple strings".

--- gcc-3.3/config.sub.old	Sun Jun  8 20:38:47 2003

+++ gcc-3.3/config.sub	Sun Jun  8 20:40:34 2003

@@ -433,9 +433,12 @@

 	crds | unos)

 		basic_machine=m68k-crds

 		;;

-	cris | cris-* | etrax*)

+	cris | etrax*)

 		basic_machine=cris-axis

 		;;

+	cris-*)

+		basic_machine=cris-`echo $basic_machine | sed 's/^[^-]*-//'`

+		;;

 	da30 | da30-*)

 		basic_machine=m68k-da30

 		;;

@@ -820,11 +823,17 @@

 	rtpc | rtpc-*)

 		basic_machine=romp-ibm

 		;;

-	s390 | s390-*)

+	s390)

 		basic_machine=s390-ibm

 		;;

-	s390x | s390x-*)

+	s390-*)

+		basic_machine=s390-`echo $basic_machine | sed 's/^[^-]*-//'`

+		;;

+	s390x)

 		basic_machine=s390x-ibm

+		;;

+	s390x-*)

+		basic_machine=s390x-`echo $basic_machine | sed 's/^[^-]*-//'`

 		;;

 	sa29200)

 		basic_machine=a29k-amd