Index: sys/sys/systm.h
===================================================================
--- sys/sys/systm.h
+++ sys/sys/systm.h
@@ -47,6 +47,7 @@
 #include <sys/queue.h>
 #include <sys/stdint.h>		/* for people using printf mainly */
 
+#ifdef _KERNEL
 __NULLABILITY_PRAGMA_PUSH
 
 extern int cold;		/* nonzero if we are doing a cold boot */
@@ -97,8 +98,9 @@
 void	kassert_panic(const char *fmt, ...)  __printflike(1, 2);
 #else
 #define kassert_panic	panic
-#endif
-#endif
+#endif /* KASSERT_PANIC_OPTIONAL */
+#endif /* defined(WITNESS) || defined(INVARIANT_SUPPORT) */
+#endif /* KERNEL */
 
 #ifdef	INVARIANTS		/* The option is always available */
 #define	KASSERT(exp,msg) do {						\
@@ -135,12 +137,6 @@
 #define	CTASSERT(x)	_Static_assert(x, "compile-time assertion failed")
 #endif
 
-#if defined(_KERNEL)
-#include <sys/param.h>		/* MAXCPU */
-#include <sys/pcpu.h>		/* curthread */
-#include <sys/kpilite.h>
-#endif
-
 /*
  * Helpful macros for quickly coming up with assertions with informative
  * panic messages.
@@ -151,6 +147,18 @@
 #define MPASS4(ex, what, file, line)					\
 	KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line))
 
+/*
+ * Align variables.
+ */
+#define	__read_mostly		__section(".data.read_mostly")
+#define	__read_frequently	__section(".data.read_frequently")
+#define	__exclusive_cache_line	__aligned(CACHE_LINE_SIZE) \
+				    __section(".data.exclusive_cache_line")
+#ifdef _KERNEL
+#include <sys/param.h>		/* MAXCPU */
+#include <sys/pcpu.h>		/* curthread */
+#include <sys/kpilite.h>
+
 /*
  * Assert that a pointer can be loaded from memory atomically.
  *
@@ -180,13 +188,6 @@
 })
 #define	SCHEDULER_STOPPED() SCHEDULER_STOPPED_TD(curthread)
 
-/*
- * Align variables.
- */
-#define	__read_mostly		__section(".data.read_mostly")
-#define	__read_frequently	__section(".data.read_frequently")
-#define	__exclusive_cache_line	__aligned(CACHE_LINE_SIZE) \
-				    __section(".data.exclusive_cache_line")
 /*
  * XXX the hints declarations are even more misplaced than most declarations
  * in this file, since they are needed in one file (per arch) and only used
@@ -629,4 +630,5 @@
 
 __NULLABILITY_PRAGMA_POP
 
+#endif
 #endif /* !_SYS_SYSTM_H_ */