--- a/setup.py
+++ b/setup.py
@@ -521,6 +521,7 @@ class PyBuildExt(build_ext):
             print("Failed to build these modules:")
             print_three_column(failed)
             print()
+            if CROSS_COMPILING: sys.exit(1)
 
         if self.failed_on_import:
             failed = self.failed_on_import[:]