diff --git a/CMakeLists.txt b/CMakeLists.txt
index d214d77f8..dbd5baa5f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -886,21 +886,23 @@ CHECK_C_SOURCE_COMPILES("#include <stdint.h>
 		return 0;
 	}" LWS_HAS_INTPTR_T)
 
-set(CMAKE_REQUIRED_FLAGS "-pthread")	
-CHECK_C_SOURCE_COMPILES("#define _GNU_SOURCE 
-	#include <pthread.h> 
-	int main(void) { 
-		pthread_t th = 0;
-		pthread_setname_np(th, NULL);
-		return 0;
-	}" LWS_HAS_PTHREAD_SETNAME_NP)
+if (LWS_HAVE_PTHREAD_H)
+	set(CMAKE_REQUIRED_FLAGS "-pthread")
+	CHECK_C_SOURCE_COMPILES("#define _GNU_SOURCE
+		#include <pthread.h>
+		int main(void) {
+			pthread_t th = 0;
+			pthread_setname_np(th, NULL);
+			return 0;
+		}" LWS_HAS_PTHREAD_SETNAME_NP)
 
-CHECK_C_SOURCE_COMPILES("#include <stddef.h>
-	#include <getopt.h> 
-	int main(void) { 
-		void *p = (void *)getopt_long;
-		return p != NULL;
-	}" LWS_HAS_GETOPT_LONG)
+	CHECK_C_SOURCE_COMPILES("#include <stddef.h>
+		#include <getopt.h>
+		int main(void) {
+			void *p = (void *)getopt_long;
+			return p != NULL;
+		}" LWS_HAS_GETOPT_LONG)
+endif()
 
 
 if (NOT PID_T_SIZE)