diff --git a/src/test/run-make/issue-10971-temps-dir/Makefile b/src/test/run-make/issue-10971-temps-dir/Makefile
index 18d8729ab0c3..f062e652a04e 100644
--- a/src/test/run-make/issue-10971-temps-dir/Makefile
+++ b/src/test/run-make/issue-10971-temps-dir/Makefile
@@ -3,6 +3,9 @@
 # Regression test for issue #10971
 # Running two invocations in parallel would overwrite each other's temp files.
 
+## clean up unused env variables which might cause harm.
+unexport RUSTC_LINKER
+
 all:
 	touch $(TMPDIR)/lib.rs