diff --git a/lib/csu/Makefile.inc b/lib/csu/Makefile.inc
index 51e9fdfa7478..078cb9f08432 100644
--- a/lib/csu/Makefile.inc
+++ b/lib/csu/Makefile.inc
@@ -2,4 +2,4 @@
 
 SSP_CFLAGS=
 
-WARNS?=	6
+.include "../Makefile.inc"
diff --git a/lib/csu/arm/Makefile b/lib/csu/arm/Makefile
index da0eb125ce83..c0182847cd04 100644
--- a/lib/csu/arm/Makefile
+++ b/lib/csu/arm/Makefile
@@ -5,12 +5,9 @@
 SRCS=		crt1.c crti.S crtn.S
 OBJS=		${SRCS:N*.h:R:S/$/.o/g}
 OBJS+=		Scrt1.o gcrt1.o
-CFLAGS+=	-Wall -Wno-unused \
-		-I${.CURDIR}/../common \
+CFLAGS+=	-I${.CURDIR}/../common \
 		-I${.CURDIR}/../../libc/include
 
-WARNS?=		2
-
 all: ${OBJS}
 
 CLEANFILES=	${OBJS}
diff --git a/lib/csu/ia64/Makefile b/lib/csu/ia64/Makefile
index d79510399dbb..781c4582d1fd 100644
--- a/lib/csu/ia64/Makefile
+++ b/lib/csu/ia64/Makefile
@@ -5,8 +5,7 @@
 SRCS=		crt1.S crti.S crtn.S
 OBJS=		${SRCS:N*.h:R:S/$/.o/g}
 OBJS+=		Scrt1.o gcrt1.o
-CFLAGS+=	-Wall -Wno-unused \
-		-I${.CURDIR}/../common \
+CFLAGS+=	-I${.CURDIR}/../common \
 		-I${.CURDIR}/../../libc/include
 
 all: ${OBJS}
diff --git a/lib/csu/mips/Makefile b/lib/csu/mips/Makefile
index da0eb125ce83..c0182847cd04 100644
--- a/lib/csu/mips/Makefile
+++ b/lib/csu/mips/Makefile
@@ -5,12 +5,9 @@
 SRCS=		crt1.c crti.S crtn.S
 OBJS=		${SRCS:N*.h:R:S/$/.o/g}
 OBJS+=		Scrt1.o gcrt1.o
-CFLAGS+=	-Wall -Wno-unused \
-		-I${.CURDIR}/../common \
+CFLAGS+=	-I${.CURDIR}/../common \
 		-I${.CURDIR}/../../libc/include
 
-WARNS?=		2
-
 all: ${OBJS}
 
 CLEANFILES=	${OBJS}
diff --git a/lib/csu/mips/crt1.c b/lib/csu/mips/crt1.c
index 7409c28e248c..fd00258b24e9 100644
--- a/lib/csu/mips/crt1.c
+++ b/lib/csu/mips/crt1.c
@@ -72,8 +72,8 @@ void __start(char **, void (*)(void), struct Struct_Obj_Entry *, struct ps_strin
 void
 __start(char **ap,
 	void (*cleanup)(void),			/* from shared loader */
-	struct Struct_Obj_Entry *obj,		/* from shared loader */
-	struct ps_strings *ps_strings)
+	struct Struct_Obj_Entry *obj __unused,	/* from shared loader */
+	struct ps_strings *ps_strings __unused)
 {
 	int argc;
 	char **argv;
diff --git a/lib/csu/powerpc/Makefile b/lib/csu/powerpc/Makefile
index 097f82df1f9b..c0182847cd04 100644
--- a/lib/csu/powerpc/Makefile
+++ b/lib/csu/powerpc/Makefile
@@ -5,8 +5,7 @@
 SRCS=		crt1.c crti.S crtn.S
 OBJS=		${SRCS:N*.h:R:S/$/.o/g}
 OBJS+=		Scrt1.o gcrt1.o
-CFLAGS+=	-Wall -Wno-unused \
-		-I${.CURDIR}/../common \
+CFLAGS+=	-I${.CURDIR}/../common \
 		-I${.CURDIR}/../../libc/include
 
 all: ${OBJS}