diff --git a/CMakeLists.txt b/CMakeLists.txt
index 505bba01..0d4fb897 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,7 +31,7 @@ endif()
 option(WITH_SSL "Include SSL support (default OpenSSL, CyaSSL if USE_CYASSL is set)" ON)
 option(USE_EXTERNAL_ZLIB "Search the system for ZLib instead of using the included one (on Windows)" OFF)
 option(USE_CYASSL "Use CyaSSL replacement for OpenSSL. When settings this, you also need to specify CYASSL_LIB and CYASSL_INCLUDE_DIRS" OFF)
-option(WITH_BUILTIN_GETIFADDRS "Use BSD getifaddrs implementation from libwebsockets... default is your libc provides it" OFF)
+option(WITHOUT_BUILTIN_GETIFADDRS "Don't use BSD getifaddrs implementation from libwebsockets if it is missing (this will result in a compilation error) ... Default is your libc provides it. On some systems such as uclibc it doesn't exist." OFF)
 option(WITHOUT_TESTAPPS "Don't build the libwebsocket-test-apps" OFF)
 option(WITHOUT_CLIENT "Don't build the client part of the library" OFF)
 option(WITHOUT_SERVER "Don't build the server part of the library" OFF)
@@ -146,10 +146,11 @@ CHECK_FUNCTION_EXISTS(strerror HAVE_STRERROR)
 CHECK_FUNCTION_EXISTS(vfork HAVE_VFORK)
 CHECK_FUNCTION_EXISTS(getifaddrs HAVE_GETIFADDRS)
 
-if (WITH_BUILTIN_GETIFADDRS)
-	if (HAVE_GETIFADDRS)
-		warning("getifaddrs already exists on the system, are you sure you want to build using the BSD version? (This is normally only needed on systems running uclibc)")
+if (NOT HAVE_GETIFADDRS)
+	if (WITHOUT_BUILTIN_GETIFADDRS)
+		message(FATAL_ERROR "No getifaddrs was found on the system. Turn off the WITHOUT_BUILTIN_GETIFADDRS compile option to use the supplied BSD version.")
 	endif()
+
 	set(LWS_BUILTIN_GETIFADDRS 1)
 endif()
 
@@ -264,7 +265,7 @@ else()
 endif()
 
 if (UNIX)
-	if (NOT WITH_BUILTIN_GETIFADDRS)
+	if (NOT HAVE_GETIFADDRS)
 		list(APPEND HDR_PRIVATE lib/getifaddrs.h)
 		list(APPEND SOURCES lib/getifaddrs.c)
 	endif()