diff --git a/cmake/CMakeLists.txt b/cmake/CMakeLists.txt
index 2c6aed06a3..ec8d5686cd 100644
--- a/cmake/CMakeLists.txt
+++ b/cmake/CMakeLists.txt
@@ -385,7 +385,7 @@ if(BUILD_IFCGEOM)
 
     # Open CASCADE
     if(WITH_OPENCASCADE)
-    if("${OCC_INCLUDE_DIR}" STREQUAL "")
+    if(NOT OCC_INCLUDE_DIR)
 	clear_wasm_sysroot()
         find_path(OCC_INCLUDE_DIR Standard_Version.hxx
             PATHS