diff -rauN a/config/makefiles/rust.mk b/config/makefiles/rust.mk
--- a/config/makefiles/rust.mk	2019-12-02 13:22:52.000000000 +0100
+++ b/config/makefiles/rust.mk	2019-12-14 11:02:19.896773114 +0100
@@ -265,15 +265,15 @@
 # the chance of proxy bypasses originating from rust code.
 # The check only works when rust code is built with -Clto.
 # Enabling sancov also causes this to fail.
-ifndef MOZ_PROFILE_GENERATE
-ifeq ($(OS_ARCH), Linux)
-ifeq (,$(rustflags_sancov))
-ifneq (,$(filter -Clto,$(cargo_rustc_flags)))
-	$(call py_action,check_binary,--target --networking $@)
-endif
-endif
-endif
-endif
+#ifndef MOZ_PROFILE_GENERATE
+#ifeq ($(OS_ARCH), Linux)
+#ifeq (,$(rustflags_sancov))
+#ifneq (,$(filter -Clto,$(cargo_rustc_flags)))
+#	$(call py_action,check_binary,--target --networking $@)
+#endif
+#endif
+#endif
+#endif
 
 force-cargo-library-check:
 	$(call CARGO_CHECK) --lib $(cargo_target_flag) $(rust_features_flag)