diff --git a/share/mk/bsd.compat.mk b/share/mk/bsd.compat.mk
index 03aa3346b2c1..d91f96c77b3f 100644
--- a/share/mk/bsd.compat.mk
+++ b/share/mk/bsd.compat.mk
@@ -8,6 +8,7 @@
 	NOCRYPT:NO_CRYPT \
 	NODOCCOMPRESS:NO_DOCCOMPRESS \
 	NOEXTRADEPEND:NO_EXTRADEPEND \
+	NOFORTH:NO_FORTH \
 	NOFSCHG:NO_FSCHG \
 	NOGAMES:NO_GAMES \
 	NOHTML:NO_HTML \
diff --git a/sys/boot/Makefile b/sys/boot/Makefile
index 5a720e8978fc..d9b9e502ee7f 100644
--- a/sys/boot/Makefile
+++ b/sys/boot/Makefile
@@ -1,6 +1,6 @@
 # $FreeBSD$
 
-.if !defined(NOFORTH)
+.if !defined(NO_FORTH)
 # Build the add-in FORTH interpreter.
 SUBDIR+=		ficl
 .endif
diff --git a/sys/boot/alpha/common/Makefile.common b/sys/boot/alpha/common/Makefile.common
index bf9a68219d05..bbe9099f7419 100644
--- a/sys/boot/alpha/common/Makefile.common
+++ b/sys/boot/alpha/common/Makefile.common
@@ -15,7 +15,7 @@ SRCS+=		dev_net.c
 
 .PATH: ${.CURDIR}/../libalpha
 
-.if !defined(NOFORTH)
+.if !defined(NO_FORTH)
 # Enable BootForth
 BOOT_FORTH=	yes
 CFLAGS+=	-DBOOT_FORTH
diff --git a/sys/boot/i386/loader/Makefile b/sys/boot/i386/loader/Makefile
index 3273e3f31bf9..036f699dbeb5 100644
--- a/sys/boot/i386/loader/Makefile
+++ b/sys/boot/i386/loader/Makefile
@@ -18,7 +18,7 @@ CFLAGS+=	-DLOADER_NFS_SUPPORT
 HAVE_PNP=	yes
 HAVE_ISABUS=	yes
 
-.if !defined(NOFORTH)
+.if !defined(NO_FORTH)
 # Enable BootForth
 BOOT_FORTH=	yes
 CFLAGS+=	-DBOOT_FORTH -I${.CURDIR}/../../ficl -I${.CURDIR}/../../ficl/i386
diff --git a/sys/boot/ia64/efi/Makefile b/sys/boot/ia64/efi/Makefile
index 9e38fde47187..652499258763 100644
--- a/sys/boot/ia64/efi/Makefile
+++ b/sys/boot/ia64/efi/Makefile
@@ -11,7 +11,7 @@ CFLAGS+=	-I${.CURDIR}/../../efi/include/${MACHINE_ARCH}
 CFLAGS+=	-I${.CURDIR}/../../efi/libefi
 CFLAGS+=	-I${.CURDIR}/../../../../lib/libstand
 
-.if !defined(NOFORTH)
+.if !defined(NO_FORTH)
 BOOT_FORTH=	yes
 CFLAGS+=	-DBOOT_FORTH
 CFLAGS+=	-I${.CURDIR}/../../ficl
diff --git a/sys/boot/ia64/ski/Makefile b/sys/boot/ia64/ski/Makefile
index 2acf551b4f2a..c6b8a170d5b3 100644
--- a/sys/boot/ia64/ski/Makefile
+++ b/sys/boot/ia64/ski/Makefile
@@ -16,7 +16,7 @@ CFLAGS+=	-I${.CURDIR}/../../efi/include
 CFLAGS+=	-I${.CURDIR}/../../efi/include/${MACHINE_ARCH}
 LDFLAGS=	-Wl,-T${.CURDIR}/ldscript.ia64
 
-.if !defined(NOFORTH)
+.if !defined(NO_FORTH)
 CFLAGS+=	-DBOOT_FORTH
 CFLAGS+=	-I${.CURDIR}/../../ficl
 CFLAGS+=	-I${.CURDIR}/../../ficl/${MACHINE_ARCH}
diff --git a/sys/boot/pc98/loader/Makefile b/sys/boot/pc98/loader/Makefile
index 6003c8d3a470..6180515a7358 100644
--- a/sys/boot/pc98/loader/Makefile
+++ b/sys/boot/pc98/loader/Makefile
@@ -20,7 +20,7 @@ CFLAGS+=	-DLOADER_NFS_SUPPORT
 HAVE_PNP=	yes
 HAVE_ISABUS=	yes
 
-.if !defined(NOFORTH)
+.if !defined(NO_FORTH)
 # Enable BootForth
 BOOT_FORTH=	yes
 CFLAGS+=	-DBOOT_FORTH -I${.CURDIR}/../../ficl -I${.CURDIR}/../../ficl/i386
diff --git a/sys/boot/powerpc/loader/Makefile b/sys/boot/powerpc/loader/Makefile
index 873d86d6bd0f..c409729a2850 100644
--- a/sys/boot/powerpc/loader/Makefile
+++ b/sys/boot/powerpc/loader/Makefile
@@ -46,7 +46,7 @@ CFLAGS+=	-DLOADER_NFS_SUPPORT
 CFLAGS+=	-DLOADER_TFTP_SUPPORT
 .endif
 
-.if !defined(NOFORTH)
+.if !defined(NO_FORTH)
 # Enable BootForth
 BOOT_FORTH=	yes
 CFLAGS+=	-DBOOT_FORTH -I${.CURDIR}/../../ficl -I${.CURDIR}/../../ficl/powerpc
diff --git a/sys/boot/powerpc/ofw/Makefile b/sys/boot/powerpc/ofw/Makefile
index 873d86d6bd0f..c409729a2850 100644
--- a/sys/boot/powerpc/ofw/Makefile
+++ b/sys/boot/powerpc/ofw/Makefile
@@ -46,7 +46,7 @@ CFLAGS+=	-DLOADER_NFS_SUPPORT
 CFLAGS+=	-DLOADER_TFTP_SUPPORT
 .endif
 
-.if !defined(NOFORTH)
+.if !defined(NO_FORTH)
 # Enable BootForth
 BOOT_FORTH=	yes
 CFLAGS+=	-DBOOT_FORTH -I${.CURDIR}/../../ficl -I${.CURDIR}/../../ficl/powerpc
diff --git a/sys/boot/sparc64/loader/Makefile b/sys/boot/sparc64/loader/Makefile
index 31129cd1412e..c8a423de2ddb 100644
--- a/sys/boot/sparc64/loader/Makefile
+++ b/sys/boot/sparc64/loader/Makefile
@@ -41,7 +41,7 @@ CFLAGS+=	-DLOADER_NFS_SUPPORT
 CFLAGS+=	-DLOADER_TFTP_SUPPORT
 .endif
 
-.if !defined(NOFORTH)
+.if !defined(NO_FORTH)
 # Enable BootForth
 BOOT_FORTH=	yes
 CFLAGS+=	-DBOOT_FORTH -I${.CURDIR}/../../ficl -I${.CURDIR}/../../ficl/sparc64