diff --git a/CMake/setup.cmake b/CMake/setup.cmake
index 493152c01..d4ee85e0b 100644
--- a/CMake/setup.cmake
+++ b/CMake/setup.cmake
@@ -122,7 +122,7 @@ if(APPLE)
   function(CHECK_OSX_MAX_ALLOWED SDK_VERSION RESULT)
     set(_result FLTK_CHECK_OSX_MAX_ALLOWED_${SDK_VERSION})
     try_compile(${_result}
-      ${CMAKE_CURRENT_BINARY_DIR}_SDK_${SDK_VERSION}
+      ${CMAKE_CURRENT_BINARY_DIR}/CHECK_OSX_MAX_ALLOWED_${SDK_VERSION}
       SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/CMake/macOSMaxAllowed.c
       COMPILE_DEFINITIONS -DSDK_VERSION_CHECK=${SDK_VERSION}
     )