diff --git a/tests/utils/stl-lit/stl-lit.in b/tests/utils/stl-lit/stl-lit.in
index c9c28dc1fce..aa8f832e2f9 100644
--- a/tests/utils/stl-lit/stl-lit.in
+++ b/tests/utils/stl-lit/stl-lit.in
@@ -29,6 +29,13 @@ sys.path.insert(0, os.path.join("@LLVM_SOURCE_DIR@", 'utils', 'lit'))
 builtin_parameters= {}
 builtin_parameters['config_map'] = config_map
 
+def assert_same_platform_for_build_and_test():
+    build_platform = '$ENV{Platform}'
+    test_platform = os.getenv('Platform', default='')
+    if build_platform != '' and test_platform != '' and build_platform != test_platform:
+        exit(f'Target platform mismatch: the STL was built for {build_platform} but tested for {test_platform}.')
+
 if __name__=='__main__':
+    assert_same_platform_for_build_and_test()
     from lit.main import main
     main(builtin_parameters)