See http://gcc.gnu.org/PR15089
"In some cases the specified register for a local variable meant to be
used with inline assembly code is not respected.  This breaks code 
relying on this feature to implement non-standard calling convension."

This fix is probably needed to properly implement linux syscalls in some architectures.

First added to crosstool by Jamie Hicks, see
http://www.handhelds.org/hypermail/kernel-discuss/current/0066.html

Index: gcc/loop.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/loop.c,v
retrieving revision 1.488.2.3
diff -u -r1.488.2.3 loop.c
--- gcc-old/gcc/loop.c	14 Feb 2004 14:46:03 -0000	1.488.2.3
+++ gcc-new/gcc/loop.c	28 Apr 2004 22:02:53 -0000
@@ -929,6 +929,7 @@
 			  || (! (GET_CODE (SET_SRC (set)) == REG
 				 && (REGNO (SET_SRC (set))
 				     < FIRST_PSEUDO_REGISTER))))
+		      && regno >= FIRST_PSEUDO_REGISTER 
 		      /* This test is not redundant; SET_SRC (set) might be
 			 a call-clobbered register and the life of REGNO
 			 might span a call.  */