diff --git a/lib/libprocstat/zfs/Makefile b/lib/libprocstat/zfs/Makefile
index 9efe8918492c..5e1ebd44d1d3 100644
--- a/lib/libprocstat/zfs/Makefile
+++ b/lib/libprocstat/zfs/Makefile
@@ -1,26 +1,30 @@
 .PATH: ${.CURDIR:H}
 
 SRCS=	zfs_defs.c
 OBJS=	zfs_defs.o
 WARNS?=	1
 
 FORTIFY_SOURCE=	0
 
-CFLAGS+= -DIN_BASE -D__KERNEL__ -D_KERNEL -I. -I${.CURDIR}
+# We fake a kernel compilation environment in order to get the definition for
+# 'zpool_t'.
+CFLAGS+= -DIN_BASE -D__KERNEL__ -D_KERNEL -UKLD_TIED -DKLD_MODULE
+CFLAGS+= -DHAVE_ISSETUGID -D_SYS_VMEM_H_
+
+CFLAGS+= -fno-builtin -nostdlib
+
+CFLAGS+= -I${.CURDIR}
 CFLAGS+= -I${SRCTOP}/sys/contrib/openzfs/include
 CFLAGS+= -I${SRCTOP}/sys/contrib/openzfs/include/os/freebsd/spl
-CFLAGS+= -I${SRCTOP}/sys/contrib/openzfs/include/os/freebsd/
 CFLAGS+= -I${SRCTOP}/sys/contrib/openzfs/include/os/freebsd/zfs
+CFLAGS+= -I${SRCTOP}/sys/contrib/openzfs/include/os/freebsd
 CFLAGS+= -I${SRCTOP}/sys/contrib/ck/include
-
-CFLAGS+= -I${SRCTOP}/sys -I.  -I..
 CFLAGS+= -I${SRCTOP}/sys/contrib/openzfs/module/icp/include
-CFLAGS+= -include ${SRCTOP}/sys/contrib/openzfs/include/os/freebsd/spl/sys/ccompile.h
-CFLAGS+= -DHAVE_ISSETUGID -D_SYS_VMEM_H_ -UKLD_TIED -DKLD_MODULE
+CFLAGS+= -I${SRCTOP}/sys -I. -I..
 
-CFLAGS+= -fno-builtin -nostdlib
+CFLAGS+= -include ${SRCTOP}/sys/contrib/openzfs/include/os/freebsd/spl/sys/ccompile.h
 
 all: ${OBJS}
 CLEANFILES= ${OBJS}
 
 .include <bsd.lib.mk>