diff --git a/lib/libc/include/nss_tls.h b/lib/libc/include/nss_tls.h
index 999d1989e68b..13ab367d06b5 100644
--- a/lib/libc/include/nss_tls.h
+++ b/lib/libc/include/nss_tls.h
@@ -75,6 +75,6 @@ name##_getstate(struct name##_state **p)			\
 	return (rv);						\
 }								\
 /* allow the macro invocation to end with a semicolon */	\
-typedef int _##name##_bmVjdGFy
+struct _clashproof_bmVjdGFy
 
 #endif /* _NSS_TLS_H_ */
diff --git a/lib/libc/net/nsdispatch.c b/lib/libc/net/nsdispatch.c
index 53619510b001..7dd908626282 100644
--- a/lib/libc/net/nsdispatch.c
+++ b/lib/libc/net/nsdispatch.c
@@ -316,9 +316,11 @@ nss_configure(void)
 	static pthread_mutex_t conf_lock = PTHREAD_MUTEX_INITIALIZER;
 	static time_t	 confmod;
 	struct stat	 statbuf;
-	int		 result;
+	int		 result, isthreaded;
 	const char	*path;
 
+	result = 0;
+	isthreaded = __isthreaded;
 #if defined(_NSS_DEBUG) && defined(_NSS_SHOOT_FOOT)
 	/* NOTE WELL:  THIS IS A SECURITY HOLE. This must only be built
 	 * for debugging purposes and MUST NEVER be used in production.
@@ -331,16 +333,20 @@ nss_configure(void)
 		return (0);
 	if (statbuf.st_mtime <= confmod)
 		return (0);
-	result = _pthread_mutex_trylock(&conf_lock);
-	if (result != 0)
-		return (0);
-	(void)_pthread_rwlock_unlock(&nss_lock);
-	result = _pthread_rwlock_wrlock(&nss_lock);
-	if (result != 0)
-		goto fin2;
+	if (isthreaded) {
+	    result = _pthread_mutex_trylock(&conf_lock);
+	    if (result != 0)
+		    return (0);
+	    (void)_pthread_rwlock_unlock(&nss_lock);
+	    result = _pthread_rwlock_wrlock(&nss_lock);
+	    if (result != 0)
+		    goto fin2;
+	}
 	_nsyyin = fopen(path, "r");
-	if (_nsyyin == NULL)
+	if (_nsyyin == NULL) {
+		result = errno;
 		goto fin;
+	}
 	VECTOR_FREE(_nsmap, &_nsmapsize, sizeof(*_nsmap),
 	    (vector_free_elem)ns_dbt_free);
 	VECTOR_FREE(_nsmod, &_nsmodsize, sizeof(*_nsmod),
@@ -353,10 +359,14 @@ nss_configure(void)
 		(void)atexit(nss_atexit);
 	confmod = statbuf.st_mtime;
 fin:
-	(void)_pthread_rwlock_unlock(&nss_lock);
-	result = _pthread_rwlock_rdlock(&nss_lock);
+	if (isthreaded) {
+	    (void)_pthread_rwlock_unlock(&nss_lock);
+	    if (result == 0)
+		    result = _pthread_rwlock_rdlock(&nss_lock);
+	}
 fin2:
-	(void)_pthread_mutex_unlock(&conf_lock);
+	if (isthreaded)
+		(void)_pthread_mutex_unlock(&conf_lock);
 	return (result);
 }
 
@@ -510,12 +520,17 @@ ns_mod_free(ns_mod *mod)
 static void
 nss_atexit(void)
 {
-	(void)_pthread_rwlock_wrlock(&nss_lock);
+	int isthreaded;
+
+	isthreaded = __isthreaded;
+	if (isthreaded)
+		(void)_pthread_rwlock_wrlock(&nss_lock);
 	VECTOR_FREE(_nsmap, &_nsmapsize, sizeof(*_nsmap),
 	    (vector_free_elem)ns_dbt_free);
 	VECTOR_FREE(_nsmod, &_nsmodsize, sizeof(*_nsmod),
 	    (vector_free_elem)ns_mod_free);
-	(void)_pthread_rwlock_unlock(&nss_lock);
+	if (isthreaded)
+		(void)_pthread_rwlock_unlock(&nss_lock);
 }
 
 
@@ -568,13 +583,16 @@ _nsdispatch(void *retval, const ns_dtab disp_tab[], const char *database,
 	const ns_src	*srclist;
 	nss_method	 method;
 	void		*mdata;
-	int		 serrno, i, result, srclistsize;
+	int		 isthreaded, serrno, i, result, srclistsize;
 
+	isthreaded = __isthreaded;
 	serrno = errno;
-	result = _pthread_rwlock_rdlock(&nss_lock);
-	if (result != 0) {
-		result = NS_UNAVAIL;
-		goto fin;
+	if (isthreaded) {
+		result = _pthread_rwlock_rdlock(&nss_lock);
+		if (result != 0) {
+			result = NS_UNAVAIL;
+			goto fin;
+		}
 	}
 	result = nss_configure();
 	if (result != 0) {
@@ -604,7 +622,8 @@ _nsdispatch(void *retval, const ns_dtab disp_tab[], const char *database,
 				break;
 		}
 	}
-	(void)_pthread_rwlock_unlock(&nss_lock);
+	if (isthreaded)
+		(void)_pthread_rwlock_unlock(&nss_lock);
 fin:
 	errno = serrno;
 	return (result);
diff --git a/lib/libc/net/nss_compat.c b/lib/libc/net/nss_compat.c
index a81ec8ab7c8d..09a2d4f8f5cc 100644
--- a/lib/libc/net/nss_compat.c
+++ b/lib/libc/net/nss_compat.c
@@ -41,6 +41,7 @@ __FBSDID("$FreeBSD$");
 #include <pthread.h>
 #include <pthread_np.h>
 #include "un-namespace.h"
+#include "libc_private.h"
 
 
 struct group;
@@ -60,7 +61,7 @@ static pthread_once_t	 _term_once_##x = PTHREAD_ONCE_INIT
 
 #define SET_TERMINATOR(x, y)						\
 do {									\
-	if (_pthread_main_np())						\
+	if (!__isthreaded || _pthread_main_np())			\
 		_term_main_##x = (y);					\
 	else {								\
 		(void)_pthread_once(&_term_once_##x, _term_create_##x);	\
@@ -69,7 +70,7 @@ do {									\
 } while (0)
 
 #define CHECK_TERMINATOR(x)					\
-(_pthread_main_np() ?						\
+(!__isthreaded || _pthread_main_np() ?				\
     (_term_main_##x) :						\
     ((void)_pthread_once(&_term_once_##x, _term_create_##x),	\
     _pthread_getspecific(_term_key_##x)))