diff -aur root-6.14.00-old/cmake/modules/SearchInstalledSoftware.cmake root-6.14.00-new/cmake/modules/SearchInstalledSoftware.cmake
--- root-6.14.00-old/cmake/modules/SearchInstalledSoftware.cmake	2018-06-13 12:10:40.000000000 +0200
+++ root-6.14.00-new/cmake/modules/SearchInstalledSoftware.cmake	2018-07-06 17:35:20.679662343 +0200
@@ -448,11 +448,7 @@
   find_package(PythonInterp ${python_version} REQUIRED)
   find_package(PythonLibs ${python_version} REQUIRED)
   if (tmva)
-    if(fail-on-missing)
-      find_package(NumPy REQUIRED)
-    else()
-      find_package(NumPy)
-    endif()
+    find_package(NumPy)
   endif()
 endif()