diff --git a/CMakeLists.txt b/CMakeLists.txt
index 814760798..ec80b2064 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -563,8 +563,10 @@ if (LWS_HAVE_PTHREAD_H AND NOT LWS_PLAT_FREERTOS)
 		set(LWS_PTHR_FLAGS "-pthread")
 	endif()
 	
-	set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS} ${LWS_PTHR_FLAGS})
-	list(APPEND LIB_LIST_AT_END ${LWS_PTHR_FLAGS})
+	set(CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES} ${LWS_PTHR_FLAGS})
+	if (NOT WIN32 AND NOT MSVC)
+		list(APPEND LIB_LIST_AT_END ${LWS_PTHR_FLAGS})
+	endif()
 
 	CHECK_C_SOURCE_COMPILES("#define _GNU_SOURCE
 		#include <pthread.h>
@@ -716,7 +718,7 @@ if (LWS_WITH_ZLIB)
 	include_directories(${ZLIB_INCLUDE_DIRS})
 	# done later at end of link list
 	# list(APPEND LIB_LIST ${ZLIB_LIBRARIES})
-	set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS} ${ZLIB_LIBRARIES})
+	set(CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES} ${ZLIB_LIBRARIES})
 	list(APPEND LIB_LIST_AT_END ${ZLIB_LIBRARIES})
 endif()