Binutils and Endianness

What configures the endianness that binutils is built as?

I have added an extra architecture type to the Config.in.arch but I can't get it past binutils

Index: target/Config.in.arch
===================================================================
@@ -203,6 +203,8 @@
        help
          Specific CPU variant to use
 
+config BR2_sh2a
+       bool "sh2a"
 config BR2_sh2a_nofpueb
        bool "sh2a_nofpueb"
 config BR2_sh2eb

@@ -509,6 +511,7 @@
        default "powerpc"       if BR2_powerpc
        default "s390"          if BR2_s390
        default "s390"          if BR2_s390x
+       default "sh2a"          if BR2_sh2a
        default "sh2a_nofpueb"  if BR2_sh2a_nofpueb
        default "sh2eb"         if BR2_sh2eb
        default "sh3"           if BR2_sh3

@@ -532,7 +535,7 @@
                            BR2_sh3 || BR2_sh4 || BR2_x86_64 || 

BR2_nios2 || \
                            BR2_sh64
        default "BIG"    if BR2_alpha || BR2_armeb || BR2_avr32 || 
BR2_m68k || BR2_mips || \
-                           BR2_powerpc || BR2_sh2a_nofpueb || BR2_sh2eb 
|| \
+                           BR2_powerpc || BR2_sh2a || BR2_sh2a_nofpueb 
|| BR2_sh2eb || \
                            BR2_sh3eb || BR2_sh4eb || BR2_sparc || 

BR2_sparc64

config BR2_GCC_TARGET_TUNE

/tmp/ccOmyORE.s:658: Internal error, aborting at /opt/buildroot-sh2a/toolchain_build_sh2a/binutils-2.18/gas/config/tc-sh.c line 4012 in md_apply_fix
tc-sh:4010: case BFD_RELOC_SH_DISP20:
tc-sh:4011: if (! target_big_endian)
tc-sh:4012: abort();

Am I missing something obvious ?

--
Kieran