Kernel builds now happen in compile/CONFIG/obj@ -> /usr/obj/... [or ./obj/,

if srctree is not rooted at /usr/src].  As a result, stock GENERIC & RAMDISK
kernels are commited to the tree, to ensure the src tree can be "readonly"
during builds, with all writes occuring inside the obj space.  config -b
options are handled by ../Makefile.inc.  The canonical new way to configure
one of these kernels is:
    % cd /sys/arch/amd64/compile/GENERIC.MP
    % doas make obj
    % make config
    % make
    % doas cp obj/bsd /bsd
The build infrastructure will use this new mechanism in a de-escalation
way using BUILDUSER.
Much help from natano and tb.

8 files changed, 36 insertions, 7 deletions

diff --git a/sys/arch/macppc/Makefile b/sys/arch/macppc/Makefile
index 32ab5e9ab62..eac34cca820 100644
--- a/sys/arch/macppc/Makefile
+++ b/sys/arch/macppc/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.11 2016/05/31 18:37:04 tedu Exp $
+#	$OpenBSD: Makefile,v 1.12 2016/10/14 18:42:58 deraadt Exp $
 
 S=	${.CURDIR}/../..
 KFILE=	GENERIC
@@ -11,7 +11,7 @@ TAGS=	${.CURDIR}/tags
 NOPROG=
 NOMAN=
 NOOBJ=
-SUBDIR=	stand
+SUBDIR=	stand compile
 
 # config the fattest kernel we can find into a temporary dir
 # to create a Makefile.  Then use make to pull some variables
diff --git a/sys/arch/macppc/compile/.cvsignore b/sys/arch/macppc/compile/.cvsignore
deleted file mode 100644
index d3160b418c1..00000000000
--- a/sys/arch/macppc/compile/.cvsignore
+++ /dev/null
@@ -1,3 +0,0 @@
-GENERIC
-GENERIC.MP
-RAMDISK
diff --git a/sys/arch/macppc/compile/GENERIC.MP/Makefile b/sys/arch/macppc/compile/GENERIC.MP/Makefile
new file mode 100644
index 00000000000..01b5f23410c
--- /dev/null
+++ b/sys/arch/macppc/compile/GENERIC.MP/Makefile
@@ -0,0 +1 @@
+.include "../Makefile.inc"
diff --git a/sys/arch/macppc/compile/GENERIC/Makefile b/sys/arch/macppc/compile/GENERIC/Makefile
new file mode 100644
index 00000000000..01b5f23410c
--- /dev/null
+++ b/sys/arch/macppc/compile/GENERIC/Makefile
@@ -0,0 +1 @@
+.include "../Makefile.inc"
diff --git a/sys/arch/macppc/compile/Makefile b/sys/arch/macppc/compile/Makefile
new file mode 100644
index 00000000000..4c1ba402478
--- /dev/null
+++ b/sys/arch/macppc/compile/Makefile
@@ -0,0 +1,8 @@
+#	$OpenBSD: Makefile,v 1.1 2016/10/14 18:43:00 deraadt Exp $
+
+.if	make(obj) || make(clean)
+SUBDIR!=find . -type d -maxdepth 1 \! \( -name . -o -name CVS \)
+#SUBDIR=GENERIC GENERIC.MP RAMDISK
+.endif
+
+.include <bsd.subdir.mk>
diff --git a/sys/arch/macppc/compile/Makefile.inc b/sys/arch/macppc/compile/Makefile.inc
new file mode 100644
index 00000000000..d79a8803ef2
--- /dev/null
+++ b/sys/arch/macppc/compile/Makefile.inc
@@ -0,0 +1,19 @@
+SYSDIR != cd ${.CURDIR}/../../../..; pwd
+CONFDIR != cd ${.CURDIR}/../../conf; pwd
+
+.if ${.CURDIR} == ${.OBJDIR}
+.PHONY: config
+config:
+	@echo make obj required first >&2
+	@false
+.elif !exists(${OBJDIR}/Makefile)
+.PHONY: config clean
+config:
+	config -b ${.OBJDIR} -s ${SYSDIR} ${CONFDIR}/${.CURDIR:T}
+
+clean:
+
+.endif
+
+.include <bsd.obj.mk>
+
diff --git a/sys/arch/macppc/compile/RAMDISK/Makefile b/sys/arch/macppc/compile/RAMDISK/Makefile
new file mode 100644
index 00000000000..01b5f23410c
--- /dev/null
+++ b/sys/arch/macppc/compile/RAMDISK/Makefile
@@ -0,0 +1 @@
+.include "../Makefile.inc"
diff --git a/sys/arch/macppc/conf/Makefile.macppc b/sys/arch/macppc/conf/Makefile.macppc
index f6ac0af8c7b..490d9fde5ba 100644
--- a/sys/arch/macppc/conf/Makefile.macppc
+++ b/sys/arch/macppc/conf/Makefile.macppc
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.macppc,v 1.73 2016/09/24 19:13:03 kettenis Exp $
+#	$OpenBSD: Makefile.macppc,v 1.74 2016/10/14 18:43:02 deraadt Exp $
 
 # For instructions on building kernels consult the config(8) and options(4)
 # manual pages.
@@ -21,7 +21,7 @@ S!=	cd ../../../..; pwd
 _machdir?=	$S/arch/${_mach}
 _archdir?=	$S/arch/${_arch}
 
-INCLUDES=	-nostdinc -I$S -I. -I$S/arch
+INCLUDES=	-nostdinc -I$S -I${.OBJDIR} -I$S/arch
 CPPFLAGS=	${INCLUDES} ${IDENT} ${PARAM} -D_KERNEL -D__${_mach}__ -MD -MP
 CWARNFLAGS=	-Werror -Wall -Wimplicit-function-declaration \
 		-Wno-main -Wno-uninitialized -Wno-pointer-sign \
@@ -125,6 +125,8 @@ lint:
 	    ${CFILES} ioconf.c param.c | \
 	    grep -v 'static function .* unused'
 
+obj:
+
 depend:
 	@touch $@