diff --git a/src/Make.pkg b/src/Make.pkg
index c6c47ffd0a4..91562af92ab 100644
--- a/src/Make.pkg
+++ b/src/Make.pkg
@@ -246,4 +246,4 @@ endif
 	$(CC) $(CFLAGS) -I . -o "$@" _obj/$*.c
 
 %.$O: %.s $(HFILES)
-	$(AS) $*.s
+	$(AS) $(AFLAGS) $*.s
diff --git a/src/cmd/Makefile b/src/cmd/Makefile
index 0b83e48312e..c2f817a916a 100644
--- a/src/cmd/Makefile
+++ b/src/cmd/Makefile
@@ -8,9 +8,12 @@ all: install
 
 # Only build tools for current architecture, and only tools written in C.
 # The tools written in Go are managed by ../pkg/Makefile.
+# We need all the C compilers for rebuilding generated files in runtime.
 DIRS=\
 	$(O)a\
-	$(O)c\
+	5c\
+	6c\
+	8c\
 	$(O)g\
 	$(O)l\
 	cc\
@@ -55,7 +58,7 @@ nuke: $(patsubst %,%.nuke,$(CLEANDIRS))
 	@echo
 	$(MAKE) -C $* install
 
-gc.install $(O)c.install: cc.install
+gc.install 5c.install 6c.install 8c.install: cc.install
 $(O)g.install: gc.install
 $(O)a.install $(O)c.install $(O)g.install: $(O)l.install
 
diff --git a/src/make.bash b/src/make.bash
index 3580d2a0bde..21189fe0e68 100755
--- a/src/make.bash
+++ b/src/make.bash
@@ -78,12 +78,18 @@ done
 bash "$GOROOT"/src/clean.bash
 
 # pkg builds libcgo and the Go programs in cmd.
-for i in lib9 libbio libmach cmd pkg
+for i in lib9 libbio libmach cmd
 do
 	echo; echo; echo %%%% making $i %%%%; echo
 	gomake -C $i install
 done
 
+echo; echo; echo %%%% making runtime generated files %%%%; echo
+gomake -C pkg/runtime -f Makefile.auto
+
+echo; echo; echo %%%% making pkg%%%%; echo
+gomake -C pkg install
+
 # Print post-install messages.
 # Implemented as a function so that all.bash can repeat the output
 # after run.bash finishes running all the tests.
diff --git a/src/pkg/runtime/Makefile b/src/pkg/runtime/Makefile
index 651fa02d0b4..75443324da2 100644
--- a/src/pkg/runtime/Makefile
+++ b/src/pkg/runtime/Makefile
@@ -4,9 +4,6 @@
 
 include ../../Make.inc
 
-# Go tool will do this for package runtime.
-CFLAGS+=-DGOOS_$(GOOS) -DGOARCH_$(GOARCH)
-
 TARG=runtime
 
 GOFILES=\
@@ -14,15 +11,13 @@ GOFILES=\
 	error.go\
 	extern.go\
 	mem.go\
-	runtime_defs.go\
 	sig.go\
 	softfloat64.go\
 	type.go\
-	version.go\
-	version_$(GOOS).go\
-	version_$(GOARCH).go\
-
-CLEANFILES+=version.go version_*.go
+	zgoarch_$(GOARCH).go\
+	zgoos_$(GOOS).go\
+	zruntime_defs_$(GOOS)_$(GOARCH).go\
+	zversion.go\
 
 OFILES_darwin=\
 	lock_sema.$O\
@@ -45,7 +40,7 @@ OFILES_plan9=\
 OFILES_windows=\
 	callback_windows_$(GOARCH).$O\
 	lock_sema.$O\
-	syscall_windows.$O\
+	zsyscall_windows_$(GOARCH).$O\
 
 # 386-specific object files
 OFILES_386=\
@@ -66,6 +61,8 @@ OFILES_arm=\
 	traceback_x86.$O\
 
 OFILES=\
+	$(OFILES_$(GOARCH))\
+	$(OFILES_$(GOOS))\
 	alg.$O\
 	asm_$(GOARCH).$O\
 	atomic_$(GOARCH).$O\
@@ -77,7 +74,6 @@ OFILES=\
 	float.$O\
 	hashmap.$O\
 	iface.$O\
-	malloc.$O\
 	mcache.$O\
 	mcentral.$O\
 	mem_$(GOOS).$O\
@@ -86,31 +82,31 @@ OFILES=\
 	mfixalloc.$O\
 	mgc0.$O\
 	mheap.$O\
-	mprof.$O\
 	msize.$O\
 	print.$O\
 	proc.$O\
 	rt0_$(GOOS)_$(GOARCH).$O\
 	rune.$O\
 	runtime.$O\
-	runtime1.$O\
-	sema.$O\
 	signal_$(GOOS)_$(GOARCH).$O\
-	sigqueue.$O\
 	slice.$O\
-	string.$O\
 	symtab.$O\
 	sys_$(GOOS)_$(GOARCH).$O\
 	thread_$(GOOS).$O\
-	time.$O\
-	$(OFILES_$(GOARCH))\
-	$(OFILES_$(GOOS))\
+	zmalloc_$(GOARCH).$O\
+	zmprof_$(GOARCH).$O\
+	zruntime1_$(GOARCH).$O\
+	zsema_$(GOARCH).$O\
+	zsigqueue_$(GOARCH).$O\
+	zstring_$(GOARCH).$O\
+	ztime_$(GOARCH).$O\
 
 AUTOHFILES=\
 	arch_GOARCH.h\
 	os_GOOS.h\
 	signals_GOOS.h\
 	defs_GOOS_GOARCH.h\
+	zasm_GOOS_GOARCH.h\
 
 HFILES=\
 	cgocall.h\
@@ -126,6 +122,10 @@ GOFILES+=$(GOFILES_$(GOOS))
 # For use by cgo.
 INSTALLFILES=$(pkgdir)/runtime.h $(pkgdir)/cgocall.h
 
+# Go tool will do this for package runtime.
+AFLAGS+=-DGOOS_$(GOOS) -DGOARCH_$(GOARCH)
+CFLAGS+=-DGOOS_$(GOOS) -DGOARCH_$(GOARCH)
+
 # special, out of the way compiler flag that means "add runtime metadata to output"
 GC+= -+
 
@@ -138,44 +138,8 @@ $(pkgdir)/%.h: %.h
 clean: clean-local
 
 clean-local:
-	rm -f goc2c mkversion version.go runtime.acid.* runtime_defs.go $$(ls *.goc | sed 's/goc$$/c/') $(AUTOHFILES)
-
-asm_$(GOARCH).h: mkasmh.sh runtime.acid.$(GOARCH)
-	./mkasmh.sh >$@.x
-	mv -f $@.x $@
-
-goc2c: goc2c.c
-	quietgcc -o $@ -I "$(GOROOT)/include" $< "$(GOROOT)/lib/lib9.a"
-
-mkversion: mkversion.c
-	quietgcc -o $@ -I "$(GOROOT)/include" $< "$(GOROOT)/lib/lib9.a"
-
-version.go: mkversion
-	GOROOT="$(GOROOT_FINAL)" ./mkversion >version.go
-
-version_$(GOARCH).go:
-	(echo 'package runtime'; echo 'const theGoarch = "$(GOARCH)"') >$@
-
-version_$(GOOS).go:
-	(echo 'package runtime'; echo 'const theGoos = "$(GOOS)"') >$@
-
-%.c:	%.goc goc2c
-	./goc2c "`pwd`/$<" > $@.tmp
-	mv -f $@.tmp $@
-
-# for discovering offsets inside structs when debugging
-runtime.acid.$(GOARCH): runtime.h proc.c $(AUTOHFILES)
-	$(CC) $(CFLAGS) -a proc.c >$@
-
-# 386 traceback is really amd64 traceback
-ifeq ($(GOARCH),386)
-traceback.$O:	amd64/traceback.c
-	$(CC) $(CFLAGS) $<
-endif
-
-runtime_defs.go: proc.c iface.c hashmap.c chan.c $(HFILES)
-	CC="$(CC)" CFLAGS="$(CFLAGS)" ./mkgodefs.sh proc.c iface.c hashmap.c chan.c > $@.x
-	mv -f $@.x $@
+	rm -f $(AUTOHFILES)
+	make -f Makefile.auto clean
 
 arch_GOARCH.h: arch_$(GOARCH).h
 	cp $^ $@
@@ -188,3 +152,6 @@ os_GOOS.h: os_$(GOOS).h
 
 signals_GOOS.h: signals_$(GOOS).h
 	cp $^ $@
+
+zasm_GOOS_GOARCH.h: zasm_$(GOOS)_$(GOARCH).h
+	cp $^ $@
diff --git a/src/pkg/runtime/Makefile.auto b/src/pkg/runtime/Makefile.auto
new file mode 100644
index 00000000000..b3b31c8ccab
--- /dev/null
+++ b/src/pkg/runtime/Makefile.auto
@@ -0,0 +1,94 @@
+# Copyright 2011 The Go Authors.  All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+GOARCHES=\
+	386\
+	amd64\
+	arm\
+
+GOOSES=\
+	darwin\
+	freebsd\
+	linux\
+	netbsd\
+	openbsd\
+	plan9\
+	windows\
+
+GOOSARCHES=\
+	darwin_386\
+	darwin_amd64\
+	freebsd_386\
+	freebsd_amd64\
+	linux_386\
+	linux_amd64\
+	linux_arm\
+	netbsd_386\
+	netbsd_amd64\
+	openbsd_386\
+	openbsd_amd64\
+	plan9_386\
+	windows_386\
+	windows_amd64\
+
+AUTO=\
+	$(GOARCHES:%=zmalloc_%.c)\
+	$(GOARCHES:%=zmprof_%.c)\
+	$(GOARCHES:%=zruntime1_%.c)\
+	$(GOARCHES:%=zsema_%.c)\
+	$(GOARCHES:%=zsigqueue_%.c)\
+	$(GOARCHES:%=zstring_%.c)\
+	$(GOARCHES:%=ztime_%.c)\
+	$(GOARCHES:%=zgoarch_%.go)\
+	$(GOOSES:%=zgoos_%.go)\
+	$(GOOSARCHES:%=zruntime_defs_%.go)\
+	$(GOOSARCHES:%=zasm_%.h)\
+	zsyscall_windows_386.c\
+	zsyscall_windows_amd64.c\
+	zversion.go\
+
+all: auto
+auto: $(AUTO)
+
+# .goc -> .c (specific to os/arch combination)
+goc2c: goc2c.c
+	quietgcc -o $@ -I "$(GOROOT)/include" $< "$(GOROOT)/lib/lib9.a"
+
+z%_386.c: %.goc goc2c
+	GOARCH=386 ./goc2c "`pwd`/$<" >$@.tmp
+	mv -f $@.tmp $@
+
+z%_amd64.c: %.goc goc2c
+	GOARCH=amd64 ./goc2c "`pwd`/$<" >$@.tmp
+	mv -f $@.tmp $@
+
+z%_arm.c: %.goc goc2c
+	GOARCH=arm ./goc2c "`pwd`/$<" >$@.tmp
+	mv -f $@.tmp $@
+
+# version files
+mkversion: mkversion.c ../../../lib/lib9.a
+	quietgcc -o $@ -I "$(GOROOT)/include" $< "$(GOROOT)/lib/lib9.a"
+
+zversion.go: mkversion
+	GOROOT="$(GOROOT_FINAL)" ./mkversion >$@
+
+zgoos_%.go:
+	(echo '// AUTO-GENERATED; run make -f Makefile.auto'; echo; echo 'package runtime'; echo; echo 'const theGoos = "$*"') >$@
+
+zgoarch_%.go:
+	(echo '// AUTO-GENERATED; run make -f Makefile.auto'; echo; echo 'package runtime'; echo; echo 'const theGoarch = "$*"') >$@
+
+# definitions of runtime structs, translated from C to Go
+zruntime_defs_%.go: proc.c iface.c hashmap.c chan.c $(HFILES) mkgodefs.sh
+	./mkgodefs.sh $* proc.c iface.c hashmap.c chan.c >$@.tmp
+	mv -f $@.tmp $@
+
+# struct field offsets #defined for assembly
+zasm_%.h: mkasmh.sh proc.c defs.h
+	./mkasmh.sh $* >$@.tmp
+	mv -f $@.tmp $@
+
+clean:
+	rm -f goc2c mkversion $(AUTO)
diff --git a/src/pkg/runtime/asm_386.s b/src/pkg/runtime/asm_386.s
index c39f365d595..52400637be9 100644
--- a/src/pkg/runtime/asm_386.s
+++ b/src/pkg/runtime/asm_386.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-#include "asm_386.h"
+#include "zasm_GOOS_GOARCH.h"
 
 TEXT _rt0_386(SB),7,$0
 	// Linux, Windows start the FPU in extended double precision.
diff --git a/src/pkg/runtime/asm_amd64.s b/src/pkg/runtime/asm_amd64.s
index d91421e9e36..9053334993a 100644
--- a/src/pkg/runtime/asm_amd64.s
+++ b/src/pkg/runtime/asm_amd64.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-#include "asm_amd64.h"
+#include "zasm_GOOS_GOARCH.h"
 
 TEXT _rt0_amd64(SB),7,$-8
 	// copy arguments forward on an even stack
diff --git a/src/pkg/runtime/asm_arm.s b/src/pkg/runtime/asm_arm.s
index 533c0744d74..b36bbe30470 100644
--- a/src/pkg/runtime/asm_arm.s
+++ b/src/pkg/runtime/asm_arm.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-#include "asm_arm.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // using frame size $-4 means do not save LR on stack.
 TEXT _rt0_arm(SB),7,$-4
diff --git a/src/pkg/runtime/defs1_linux.go b/src/pkg/runtime/defs1_linux.go
index 6d84e84d768..451817a67a3 100644
--- a/src/pkg/runtime/defs1_linux.go
+++ b/src/pkg/runtime/defs1_linux.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
 Input to cgo -cdefs
 
diff --git a/src/pkg/runtime/defs2_linux.go b/src/pkg/runtime/defs2_linux.go
index 1fafb7bfc1c..9b07029556d 100644
--- a/src/pkg/runtime/defs2_linux.go
+++ b/src/pkg/runtime/defs2_linux.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
  * Input to cgo -cdefs
 
diff --git a/src/pkg/runtime/defs_arm_linux.go b/src/pkg/runtime/defs_arm_linux.go
index 35f74e8dbac..2063efb067d 100644
--- a/src/pkg/runtime/defs_arm_linux.go
+++ b/src/pkg/runtime/defs_arm_linux.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
 Input to cgo.
 On a Debian Lenny arm linux distribution:
diff --git a/src/pkg/runtime/defs_darwin.go b/src/pkg/runtime/defs_darwin.go
index 6cd988def24..3f3e41d86b1 100644
--- a/src/pkg/runtime/defs_darwin.go
+++ b/src/pkg/runtime/defs_darwin.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
 Input to cgo.
 
diff --git a/src/pkg/runtime/defs_freebsd.go b/src/pkg/runtime/defs_freebsd.go
index ee80bb28558..306e32197e4 100644
--- a/src/pkg/runtime/defs_freebsd.go
+++ b/src/pkg/runtime/defs_freebsd.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
 Input to cgo.
 
diff --git a/src/pkg/runtime/defs_linux.go b/src/pkg/runtime/defs_linux.go
index bbaab2d33e7..c0275e1114a 100644
--- a/src/pkg/runtime/defs_linux.go
+++ b/src/pkg/runtime/defs_linux.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
 Input to cgo -cdefs
 
diff --git a/src/pkg/runtime/defs_netbsd.go b/src/pkg/runtime/defs_netbsd.go
index 4fb3a046346..47c30cf101f 100644
--- a/src/pkg/runtime/defs_netbsd.go
+++ b/src/pkg/runtime/defs_netbsd.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
 Input to cgo.
 
diff --git a/src/pkg/runtime/defs_openbsd.go b/src/pkg/runtime/defs_openbsd.go
index 4fb3a046346..47c30cf101f 100644
--- a/src/pkg/runtime/defs_openbsd.go
+++ b/src/pkg/runtime/defs_openbsd.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
 Input to cgo.
 
diff --git a/src/pkg/runtime/defs_windows.go b/src/pkg/runtime/defs_windows.go
index e23e4207de8..0d525b9322f 100644
--- a/src/pkg/runtime/defs_windows.go
+++ b/src/pkg/runtime/defs_windows.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
 Input to cgo.
 
diff --git a/src/pkg/runtime/goc2c.c b/src/pkg/runtime/goc2c.c
index fcac9c0600a..f1d07f61b36 100644
--- a/src/pkg/runtime/goc2c.c
+++ b/src/pkg/runtime/goc2c.c
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 /*
  * Translate a .goc file into a .c file.  A .goc file is a combination
  * of a limited form of Go with C.
@@ -742,6 +744,7 @@ main(int argc, char **argv)
 		}
 	}
 
+	printf("// AUTO-GENERATED; run make\n\n");
 	process_file();
 	exits(0);
 }
diff --git a/src/pkg/runtime/lock_futex.c b/src/pkg/runtime/lock_futex.c
index 375b7d7d7c8..c6b64ca6de7 100644
--- a/src/pkg/runtime/lock_futex.c
+++ b/src/pkg/runtime/lock_futex.c
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build freebsd linux
+
 #include "runtime.h"
 
 // This implementation depends on OS-specific implementations of
diff --git a/src/pkg/runtime/lock_sema.c b/src/pkg/runtime/lock_sema.c
index 8875b17a245..ae229ec728c 100644
--- a/src/pkg/runtime/lock_sema.c
+++ b/src/pkg/runtime/lock_sema.c
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build darwin netbsd openbsd plan9 windows
+
 #include "runtime.h"
 
 // This implementation depends on OS-specific implementations of
diff --git a/src/pkg/runtime/mkasmh.sh b/src/pkg/runtime/mkasmh.sh
index 920e79a0245..3f6c2b2d2b8 100755
--- a/src/pkg/runtime/mkasmh.sh
+++ b/src/pkg/runtime/mkasmh.sh
@@ -5,9 +5,28 @@
 
 set -e
 
+SYS=$1
+export GOOS=$(echo $SYS | sed 's/_.*//')
+export GOARCH=$(echo $SYS | sed 's/.*_//')
+shift
+
+case "$GOARCH" in
+386) CC=8c;;
+amd64) CC=6c;;
+arm) CC=5c;;
+esac
+export CC
+
+export CFLAGS="-Dos_$GOOS -Darch_$GOARCH"
+
+cp arch_$GOARCH.h arch_GOARCH.h
+cp defs_${GOOS}_$GOARCH.h defs_GOOS_GOARCH.h
+cp os_$GOOS.h os_GOOS.h
+cp signals_$GOOS.h signals_GOOS.h
+
 cat <<'EOF'
 // Assembly constants.
-// AUTOMATICALLY GENERATED BY mkasmh.sh DURING BUILD
+// AUTO-GENERATED; run make -f Makefile.auto
 
 EOF
 
@@ -91,6 +110,7 @@ arm)
 esac
 echo
 
+$CC $CFLAGS -a proc.c |
 awk '
 { gsub(/\r/, ""); }
 /^aggr G$/ { aggr="g" }
@@ -109,5 +129,6 @@ aggr != "" && /^	/ {
 	offset=$(NF-1);
 	printf("#define %s_%s %s\n", aggr, name, offset);
 }
-' runtime.acid.$GOARCH
+'
 
+rm -f arch_GOARCH.h defs_GOOS_GOARCH.h os_GOOS.h signals_GOOS.h
diff --git a/src/pkg/runtime/mkgodefs.sh b/src/pkg/runtime/mkgodefs.sh
index b6e97213e0c..87c31f28b6b 100755
--- a/src/pkg/runtime/mkgodefs.sh
+++ b/src/pkg/runtime/mkgodefs.sh
@@ -5,10 +5,28 @@
 
 set -e
 
+SYS=$1
+export GOOS=$(echo $SYS | sed 's/_.*//')
+export GOARCH=$(echo $SYS | sed 's/.*_//')
+shift
+
+case "$GOARCH" in
+386) CC=8c;;
+amd64) CC=6c;;
+arm) CC=5c;;
+esac
+export CC
+
+export CFLAGS="-DGOOS_$GOOS -DGOARCH_$GOARCH"
+
+cp arch_$GOARCH.h arch_GOARCH.h
+cp defs_${GOOS}_$GOARCH.h defs_GOOS_GOARCH.h
+cp os_$GOOS.h os_GOOS.h
+cp signals_$GOOS.h signals_GOOS.h
+
 cat <<EOF
 // Go definitions for C variables and types.
-// AUTOMATICALLY GENERATED BY THE FOLLOWING COMMAND. DO NOT EDIT.
-// CC="$CC" CFLAGS="$CFLAGS" ./mkgodefs.sh $@
+// AUTO-GENERATED; run make -f Makefile.auto
 
 package runtime
 import "unsafe"
@@ -37,3 +55,5 @@ skip {
 
 {print}
 '
+
+rm -f arch_GOARCH.h defs_GOOS_GOARCH.h os_GOOS.h signals_GOOS.h
diff --git a/src/pkg/runtime/mkversion.c b/src/pkg/runtime/mkversion.c
index 0d96aa3569e..931302187f9 100644
--- a/src/pkg/runtime/mkversion.c
+++ b/src/pkg/runtime/mkversion.c
@@ -1,8 +1,14 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
 #include <u.h>
 #include <libc.h>
 
 char *template =
-	"// generated by mkversion.c; do not edit.\n"
+	"// AUTO-GENERATED; run make -f Makefile.auto\n\n"
 	"package runtime\n"
 	"const defaultGoroot = `%s`\n"
 	"const theVersion = \"%s\"\n";
diff --git a/src/pkg/runtime/rt0_windows_amd64.s b/src/pkg/runtime/rt0_windows_amd64.s
index 5dc6b6e51bf..dc1408adc35 100644
--- a/src/pkg/runtime/rt0_windows_amd64.s
+++ b/src/pkg/runtime/rt0_windows_amd64.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-#include "asm_amd64.h"
+#include "zasm_GOOS_GOARCH.h"
 
 TEXT	_rt0_amd64_windows(SB),7,$-8
 	MOVQ	$_rt0_amd64(SB), AX
diff --git a/src/pkg/runtime/signal_darwin_amd64.c b/src/pkg/runtime/signal_darwin_amd64.c
index fd75e78454c..c7621ddcaf2 100644
--- a/src/pkg/runtime/signal_darwin_amd64.c
+++ b/src/pkg/runtime/signal_darwin_amd64.c
@@ -152,7 +152,7 @@ sigaction(int32 i, void (*fn)(int32, Siginfo*, void*, G*), bool restart)
 		sa.sa_flags |= SA_RESTART;
 	sa.sa_mask = ~0ULL;
 	sa.sa_tramp = runtime·sigtramp;	// runtime·sigtramp's job is to call into real handler
-	*(uintptr*)&sa.__sigaction_u = (uintptr)fn;
+	*(uintptr*)sa.__sigaction_u = (uintptr)fn;
 	runtime·sigaction(i, &sa, nil);
 }
 
diff --git a/src/pkg/runtime/sys_darwin_386.s b/src/pkg/runtime/sys_darwin_386.s
index 9a513468a0c..6ce1ba5533c 100644
--- a/src/pkg/runtime/sys_darwin_386.s
+++ b/src/pkg/runtime/sys_darwin_386.s
@@ -6,7 +6,7 @@
 // See http://fxr.watson.org/fxr/source/bsd/kern/syscalls.c?v=xnu-1228
 // or /usr/include/sys/syscall.h (on a Mac) for system call numbers.
 
-#include "asm_386.h"
+#include "zasm_GOOS_GOARCH.h"
 
 TEXT runtime·notok(SB),7,$0
 	MOVL	$0xf1, 0xf1
diff --git a/src/pkg/runtime/sys_darwin_amd64.s b/src/pkg/runtime/sys_darwin_amd64.s
index ac777656c54..86f99366148 100644
--- a/src/pkg/runtime/sys_darwin_amd64.s
+++ b/src/pkg/runtime/sys_darwin_amd64.s
@@ -11,7 +11,7 @@
 // The high 8 bits specify the kind of system call: 1=Mach, 2=BSD, 3=Machine-Dependent.
 //
 
-#include "asm_amd64.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // Exit the entire program (like C exit)
 TEXT runtime·exit(SB),7,$0
diff --git a/src/pkg/runtime/sys_freebsd_386.s b/src/pkg/runtime/sys_freebsd_386.s
index 9833784efce..cec7a3e8e7a 100644
--- a/src/pkg/runtime/sys_freebsd_386.s
+++ b/src/pkg/runtime/sys_freebsd_386.s
@@ -6,7 +6,7 @@
 // /usr/src/sys/kern/syscalls.master for syscall numbers.
 //
 
-#include "asm_386.h"
+#include "zasm_GOOS_GOARCH.h"
 	
 TEXT runtime·sys_umtx_op(SB),7,$-4
 	MOVL	$454, AX
diff --git a/src/pkg/runtime/sys_freebsd_amd64.s b/src/pkg/runtime/sys_freebsd_amd64.s
index 991c33c8254..c96b2f4d6bb 100644
--- a/src/pkg/runtime/sys_freebsd_amd64.s
+++ b/src/pkg/runtime/sys_freebsd_amd64.s
@@ -6,7 +6,7 @@
 // /usr/src/sys/kern/syscalls.master for syscall numbers.
 //
 
-#include "asm_amd64.h"
+#include "zasm_GOOS_GOARCH.h"
 	
 TEXT runtime·sys_umtx_op(SB),7,$0
 	MOVQ 8(SP), DI
diff --git a/src/pkg/runtime/sys_linux_386.s b/src/pkg/runtime/sys_linux_386.s
index 1763143f9e3..b745bc502e6 100644
--- a/src/pkg/runtime/sys_linux_386.s
+++ b/src/pkg/runtime/sys_linux_386.s
@@ -6,7 +6,7 @@
 // System calls and other sys.stuff for 386, Linux
 //
 
-#include "asm_386.h"
+#include "zasm_GOOS_GOARCH.h"
 
 TEXT runtime·exit(SB),7,$0
 	MOVL	$252, AX	// syscall number
diff --git a/src/pkg/runtime/sys_linux_amd64.s b/src/pkg/runtime/sys_linux_amd64.s
index d55518686ca..ef7bb2864c0 100644
--- a/src/pkg/runtime/sys_linux_amd64.s
+++ b/src/pkg/runtime/sys_linux_amd64.s
@@ -6,7 +6,7 @@
 // System calls and other sys.stuff for AMD64, Linux
 //
 
-#include "asm_amd64.h"
+#include "zasm_GOOS_GOARCH.h"
 
 TEXT runtime·exit(SB),7,$0-8
 	MOVL	8(SP), DI
diff --git a/src/pkg/runtime/sys_linux_arm.s b/src/pkg/runtime/sys_linux_arm.s
index d0b36dedf95..e0e4135b54c 100644
--- a/src/pkg/runtime/sys_linux_arm.s
+++ b/src/pkg/runtime/sys_linux_arm.s
@@ -6,7 +6,7 @@
 // System calls and other sys.stuff for arm, Linux
 //
 
-#include "asm_arm.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // OABI
 //#define SYS_BASE 0x00900000
diff --git a/src/pkg/runtime/sys_netbsd_386.s b/src/pkg/runtime/sys_netbsd_386.s
index bcb4fc5e719..63228610243 100644
--- a/src/pkg/runtime/sys_netbsd_386.s
+++ b/src/pkg/runtime/sys_netbsd_386.s
@@ -6,7 +6,7 @@
 // /usr/src/sys/kern/syscalls.master for syscall numbers.
 //
 
-#include "asm_386.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // Exit the entire program (like C exit)
 TEXT runtime·exit(SB),7,$-4
diff --git a/src/pkg/runtime/sys_netbsd_amd64.s b/src/pkg/runtime/sys_netbsd_amd64.s
index 20817711fba..7abeb159b1e 100644
--- a/src/pkg/runtime/sys_netbsd_amd64.s
+++ b/src/pkg/runtime/sys_netbsd_amd64.s
@@ -6,7 +6,7 @@
 // /usr/src/sys/kern/syscalls.master for syscall numbers.
 //
 
-#include "asm_amd64.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // int64 rfork_thread(int32 flags, void *stack, M *m, G *g, void (*fn)(void));
 TEXT runtime·rfork_thread(SB),7,$0
diff --git a/src/pkg/runtime/sys_openbsd_386.s b/src/pkg/runtime/sys_openbsd_386.s
index ae3275c852f..d49d32b95a1 100644
--- a/src/pkg/runtime/sys_openbsd_386.s
+++ b/src/pkg/runtime/sys_openbsd_386.s
@@ -6,7 +6,7 @@
 // /usr/src/sys/kern/syscalls.master for syscall numbers.
 //
 
-#include "asm_386.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // Exit the entire program (like C exit)
 TEXT runtime·exit(SB),7,$-4
diff --git a/src/pkg/runtime/sys_openbsd_amd64.s b/src/pkg/runtime/sys_openbsd_amd64.s
index f568ba4312c..5bf2e813e81 100644
--- a/src/pkg/runtime/sys_openbsd_amd64.s
+++ b/src/pkg/runtime/sys_openbsd_amd64.s
@@ -6,7 +6,7 @@
 // /usr/src/sys/kern/syscalls.master for syscall numbers.
 //
 
-#include "asm_amd64.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // int64 rfork_thread(int32 flags, void *stack, M *m, G *g, void (*fn)(void));
 TEXT runtime·rfork_thread(SB),7,$0
diff --git a/src/pkg/runtime/sys_plan9_386.s b/src/pkg/runtime/sys_plan9_386.s
index 8c773eee9df..94c36aa4100 100644
--- a/src/pkg/runtime/sys_plan9_386.s
+++ b/src/pkg/runtime/sys_plan9_386.s
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 #include "defs_GOOS_GOARCH.h"
-#include "asm_386.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // setldt(int entry, int address, int limit)
 TEXT runtime·setldt(SB),7,$0
diff --git a/src/pkg/runtime/sys_windows_386.s b/src/pkg/runtime/sys_windows_386.s
index 307b93d5c7e..c864c7f83c9 100644
--- a/src/pkg/runtime/sys_windows_386.s
+++ b/src/pkg/runtime/sys_windows_386.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-#include "asm_386.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // void runtime·asmstdcall(void *c);
 TEXT runtime·asmstdcall(SB),7,$0
diff --git a/src/pkg/runtime/sys_windows_amd64.s b/src/pkg/runtime/sys_windows_amd64.s
index 508759ff8ff..e2a518884d7 100644
--- a/src/pkg/runtime/sys_windows_amd64.s
+++ b/src/pkg/runtime/sys_windows_amd64.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-#include "asm_amd64.h"
+#include "zasm_GOOS_GOARCH.h"
 
 // maxargs should be divisible by 2, as Windows stack
 // must be kept 16-byte aligned on syscall entry.