diff --git a/flang/test/CMakeLists.txt b/flang/test/CMakeLists.txt
--- a/flang/test/CMakeLists.txt
+++ b/flang/test/CMakeLists.txt
@@ -32,7 +32,7 @@
 )
 set_target_properties(check-flang PROPERTIES FOLDER "Tests")
 
-add_lit_testsuites(FLANG ${CMAKE_CURRENT_SOURCE_DIR}
+add_lit_testsuites(FLANG ${CMAKE_CURRENT_BINARY_DIR}
   PARAMS ${FLANG_TEST_PARAMS}
   DEPENDS ${FLANG_TEST_DEPENDS})