--- gcc/config/arm/t-arm-elf.orig	2013-01-10 21:38:27.000000000 +0100
+++ gcc/config/arm/t-arm-elf	2013-06-02 00:02:10.473472897 +0200
@@ -18,73 +18,29 @@
 
 MULTILIB_OPTIONS     = marm/mthumb
 MULTILIB_DIRNAMES    = arm thumb
-MULTILIB_EXCEPTIONS  = 
-MULTILIB_MATCHES     =
 
-#MULTILIB_OPTIONS     += mcpu=fa526/mcpu=fa626/mcpu=fa606te/mcpu=fa626te/mcpu=fmp626/mcpu=fa726te
-#MULTILIB_DIRNAMES    += fa526 fa626 fa606te fa626te fmp626 fa726te
-#MULTILIB_EXCEPTIONS  += *mthumb*/*mcpu=fa526 *mthumb*/*mcpu=fa626
-
-#MULTILIB_OPTIONS      += march=armv7
-#MULTILIB_DIRNAMES     += thumb2
-#MULTILIB_EXCEPTIONS   += march=armv7* marm/*march=armv7*
-#MULTILIB_MATCHES      += march?armv7=march?armv7-a
-#MULTILIB_MATCHES      += march?armv7=march?armv7-r
-#MULTILIB_MATCHES      += march?armv7=march?armv7-m
-#MULTILIB_MATCHES      += march?armv7=mcpu?cortex-a8
-#MULTILIB_MATCHES      += march?armv7=mcpu?cortex-r4
-#MULTILIB_MATCHES      += march?armv7=mcpu?cortex-m3
-
-# Not quite true.  We can support hard-vfp calling in Thumb2, but how do we
-# express that here?  Also, we really need architecture v5e or later
-# (mcrr etc).
-MULTILIB_OPTIONS       += mfloat-abi=hard
-MULTILIB_DIRNAMES      += fpu
-MULTILIB_EXCEPTIONS    += *mthumb/*mfloat-abi=hard*
-#MULTILIB_EXCEPTIONS    += *mcpu=fa526/*mfloat-abi=hard*
-#MULTILIB_EXCEPTIONS    += *mcpu=fa626/*mfloat-abi=hard*
-
-# MULTILIB_OPTIONS    += mcpu=ep9312
-# MULTILIB_DIRNAMES   += ep9312
-# MULTILIB_EXCEPTIONS += *mthumb/*mcpu=ep9312*
-# 	
-# MULTILIB_OPTIONS     += mlittle-endian/mbig-endian
-# MULTILIB_DIRNAMES    += le be
-# MULTILIB_MATCHES     += mbig-endian=mbe mlittle-endian=mle
-# 
-# MULTILIB_OPTIONS    += mfloat-abi=hard/mfloat-abi=soft
-# MULTILIB_DIRNAMES   += fpu soft
-# MULTILIB_EXCEPTIONS += *mthumb/*mfloat-abi=hard*
-# 
-# MULTILIB_OPTIONS    += mno-thumb-interwork/mthumb-interwork
-# MULTILIB_DIRNAMES   += normal interwork
-# 
-# MULTILIB_OPTIONS    += fno-leading-underscore/fleading-underscore
-# MULTILIB_DIRNAMES   += elf under
-# 
-# MULTILIB_OPTIONS    += mcpu=arm7
-# MULTILIB_DIRNAMES   += nofmult
-# MULTILIB_EXCEPTIONS += *mthumb*/*mcpu=arm7*
-# # Note: the multilib_exceptions matches both -mthumb and
-# # -mthumb-interwork
-# #
-# # We have to match all the arm cpu variants which do not have the
-# # multiply instruction and treat them as if the user had specified
-# # -mcpu=arm7.  Note that in the following the ? is interpreted as
-# # an = for the purposes of matching command line options.
-# # FIXME: There ought to be a better way to do this.
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm7d
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm7di
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm70
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm700
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm700i
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm710
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm710c
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm7100
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm7500
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm7500fe
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm6
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm60
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm600
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm610
-# MULTILIB_MATCHES    += mcpu?arm7=mcpu?arm620
+# Only we don't actually want any ARM libraries.  Or vanilla thumb libraries.
+MULTILIB_EXCEPTIONS  = marm* mthumb
+
+# Build with any one of arm7tdmi, M0, M3 or M4 support.
+MULTILIB_OPTIONS    += mcpu=arm7tdmi-s/mcpu=cortex-m0/mcpu=cortex-m3/mcpu=cortex-m4
+MULTILIB_DIRNAMES   += arm7tdmi-s cortex-m0 cortex-m3 cortex-m4
+
+# These don't make any sense without thumb, because GCC likes to
+# tell you that you have to supply another commandline argument
+# rather than just setting it itself.
+MULTILIB_EXCEPTIONS += mcpu=arm7tdmi-s* mcpu=cortex-m0* mcpu=cortex-m3* mcpu=cortex-m4*
+
+# All this just to get mfloat-abi=hard mfpu=fpv4-sp-d16 only specified for the M4
+MULTILIB_OPTIONS    += mfloat-abi=hard mfpu=fpv4-sp-d16
+MULTILIB_DIRNAMES   += float-abi-hard fpuv4-sp-d16
+MULTILIB_EXCEPTIONS += mfloat* mthumb/mfloat*
+MULTILIB_EXCEPTIONS += mfpu* mthumb/mfpu*
+MULTILIB_EXCEPTIONS += mthumb/mcpu=cortex-m4/mfloat-abi=hard
+MULTILIB_EXCEPTIONS += mthumb/mcpu=cortex-m4/mfpu=fpv4-sp-d16
+MULTILIB_EXCEPTIONS += *arm7tdmi-s*mfloat-abi* *arm7tdmi-s*mfpu*
+MULTILIB_EXCEPTIONS += *cortex-m3*mfloat-abi* *cortex-m3*mfpu*
+MULTILIB_EXCEPTIONS += *cortex-m0*mfloat-abi* *cortex-m0*mfpu*
+
+EXTRA_MULTILIB_PARTS = crtbegin.o crtend.o crti.o crtn.o
+