diff --git a/unit_tests/unit_test_rules.mk b/unit_tests/unit_test_rules.mk
index 69594c6fba..6172a96ebe 100644
--- a/unit_tests/unit_test_rules.mk
+++ b/unit_tests/unit_test_rules.mk
@@ -63,7 +63,7 @@ endif
 
 # C++ specific options here (added to USE_OPT).
 ifeq ($(USE_CPPOPT),)
-  USE_CPPOPT = -std=gnu++2a -fno-rtti -fpermissive -fno-use-cxa-atexit
+  USE_CPPOPT = -std=gnu++2a -fno-rtti -fno-use-cxa-atexit
 endif
 
 # Enable this if you want the linker to remove unused code and data