O64 keeps old ABI argument registers and 32 bit pointers; UHI context
classification must follow O32, not N32 or N64.
Index: libgloss/mips/include/mips/hal.h
--- libgloss/mips/include/mips/hal.h.orig
+++ libgloss/mips/include/mips/hal.h
@@ -32,7 +32,7 @@
 #include <mips/asm.h>
 #include <mips/m32c0.h>
 
-#if _MIPS_SIM == _ABIO32
+#if _MIPS_SIM == _ABIO32 || _MIPS_SIM == _ABIO64
 #define UHI_ABI 0
 #elif _MIPS_SIM == _ABIN32
 #define UHI_ABI 1
