diff --git a/ports/openal-soft/cmake-3-11.patch b/ports/openal-soft/cmake-3-11.patch
new file mode 100644
index 000000000..07f7e6936
--- /dev/null
+++ b/ports/openal-soft/cmake-3-11.patch
@@ -0,0 +1,14 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index a871f4c..f9f6b34 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -965,7 +965,8 @@ OPTION(ALSOFT_REQUIRE_DSOUND "Require DirectSound backend" OFF)
+ OPTION(ALSOFT_REQUIRE_MMDEVAPI "Require MMDevApi backend" OFF)
+ IF(HAVE_WINDOWS_H)
+     # Check MMSystem backend
+-    CHECK_INCLUDE_FILES("windows.h;mmsystem.h" HAVE_MMSYSTEM_H -D_WIN32_WINNT=0x0502)
++    set(CMAKE_REQUIRED_DEFINITIONS -D_WIN32_WINNT=0x0502)
++    CHECK_INCLUDE_FILES("windows.h;mmsystem.h" HAVE_MMSYSTEM_H)
+     IF(HAVE_MMSYSTEM_H)
+         CHECK_SHARED_FUNCTION_EXISTS(waveOutOpen "windows.h;mmsystem.h" winmm "" HAVE_LIBWINMM)
+         IF(HAVE_LIBWINMM)
diff --git a/ports/openal-soft/portfile.cmake b/ports/openal-soft/portfile.cmake
index b1421f1f5..527b4ba60 100644
--- a/ports/openal-soft/portfile.cmake
+++ b/ports/openal-soft/portfile.cmake
@@ -11,8 +11,12 @@ vcpkg_from_github(
     HEAD_REF master
 )
 
-vcpkg_apply_patches(SOURCE_PATH ${SOURCE_PATH}
-    PATCHES ${CMAKE_CURRENT_LIST_DIR}/dont-export-symbols-in-static-build.patch)
+vcpkg_apply_patches(
+    SOURCE_PATH ${SOURCE_PATH}
+    PATCHES
+        ${CMAKE_CURRENT_LIST_DIR}/dont-export-symbols-in-static-build.patch
+        ${CMAKE_CURRENT_LIST_DIR}/cmake-3-11.patch
+)
 
 if(VCPKG_LIBRARY_LINKAGE STREQUAL "dynamic")
     set(OPENAL_LIBTYPE "SHARED")