diff --git a/CMake/Platforms/WindowsCache.cmake b/CMake/Platforms/WindowsCache.cmake
index a9930f0b2a..dc46753685 100644
--- a/CMake/Platforms/WindowsCache.cmake
+++ b/CMake/Platforms/WindowsCache.cmake
@@ -70,6 +70,7 @@ if(NOT UNIX)
     set(HAVE_UTIME 1)
     set(HAVE_RAND_EGD 0)
     set(HAVE_GMTIME_R 0)
+    set(HAVE_GETADDRINFO_THREADSAFE 1)
     set(HAVE_GETHOSTBYNAME_R 0)
     set(HAVE_SIGNAL 1)
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index e1704e34ac..0ee96db6bb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1045,6 +1045,9 @@ check_symbol_exists(_strtoi64      "${CURL_INCLUDES}" HAVE__STRTOI64)
 check_symbol_exists(strerror_r     "${CURL_INCLUDES}" HAVE_STRERROR_R)
 check_symbol_exists(siginterrupt   "${CURL_INCLUDES}" HAVE_SIGINTERRUPT)
 check_symbol_exists(getaddrinfo    "${CURL_INCLUDES}" HAVE_GETADDRINFO)
+if(NOT HAVE_GETADDRINFO)
+  set(HAVE_GETADDRINFO_THREADSAFE OFF)
+endif()
 check_symbol_exists(freeaddrinfo   "${CURL_INCLUDES}" HAVE_FREEADDRINFO)
 check_symbol_exists(pipe           "${CURL_INCLUDES}" HAVE_PIPE)
 check_symbol_exists(ftruncate      "${CURL_INCLUDES}" HAVE_FTRUNCATE)
diff --git a/lib/curl_config.h.cmake b/lib/curl_config.h.cmake
index 5ac20dff0b..3ba14923cd 100644
--- a/lib/curl_config.h.cmake
+++ b/lib/curl_config.h.cmake
@@ -195,6 +195,9 @@
 /* Define to 1 if you have a working getaddrinfo function. */
 #cmakedefine HAVE_GETADDRINFO 1
 
+/* Define to 1 if the getaddrinfo function is threadsafe. */
+#cmakedefine HAVE_GETADDRINFO_THREADSAFE 1
+
 /* Define to 1 if you have the `geteuid' function. */
 #cmakedefine HAVE_GETEUID 1