diff --git a/gnu/packages/rust.scm b/gnu/packages/rust.scm
index df5d803b6b..8c5abfcbae 100644
--- a/gnu/packages/rust.scm
+++ b/gnu/packages/rust.scm
@@ -186,7 +186,9 @@ in turn be used to build the final Rust.")
                   "#[ignore]\nfn connect_timeout_unroutable"))
                ;; <https://lists.gnu.org/archive/html/guix-devel/2017-06/msg00222.html>
                (substitute* "src/libstd/sys/unix/process/process_common.rs"
-                 (("fn test_process_mask") "#[ignore]\nfn test_process_mask"))
+                (("#\\[cfg_attr\\(target_arch = \"arm\", ignore\\)\\]
+    fn test_process_mask") "#[ignore]
+    fn test_process_mask"))
                ;; Our ld-wrapper cannot process non-UTF8 bytes in LIBRARY_PATH.
                ;; <https://lists.gnu.org/archive/html/guix-devel/2017-06/msg00193.html>
                (delete-file-recursively "src/test/run-make/linker-output-non-utf8")