diff --git a/scripts/run_clang_tidy_format.sh b/scripts/run_clang_tidy_format.sh
index aecda51..664e989 100755
--- a/scripts/run_clang_tidy_format.sh
+++ b/scripts/run_clang_tidy_format.sh
@@ -26,7 +26,7 @@
 else
 	PARALLEL_JOBS=$(sysctl -n kern.smp.cpus)
 fi
-DIRECTORIES="sdk tests examples"
+DIRECTORIES="sdk tests examples tests.extra"
 # Standard headers should be included once we move to a clang-tidy that
 # supports NOLINTBEGIN to disable specific checks over a whole file.
 # In particular, modernize-redundant-void-arg should be disabled in any header
diff --git a/tests.extra/regress-thread_exit_IRQ/helper.cc b/tests.extra/regress-thread_exit_IRQ/helper.cc
index 023b4fe..0f065eb 100644
--- a/tests.extra/regress-thread_exit_IRQ/helper.cc
+++ b/tests.extra/regress-thread_exit_IRQ/helper.cc
@@ -1,5 +1,5 @@
 #include "helper.h"
-[[cheri::interrupt_state(enabled)]] void* help(void)
+[[cheri::interrupt_state(enabled)]] void *help()
 {
 	return __builtin_return_address(0);
 }
diff --git a/tests.extra/regress-thread_exit_IRQ/helper.h b/tests.extra/regress-thread_exit_IRQ/helper.h
index 578659e..0eaf329 100644
--- a/tests.extra/regress-thread_exit_IRQ/helper.h
+++ b/tests.extra/regress-thread_exit_IRQ/helper.h
@@ -1,2 +1,2 @@
 #include <compartment.h>
-void* __cheri_compartment("helper") help(void);
+void *__cheri_compartment("helper") help();
diff --git a/tests.extra/regress-thread_exit_IRQ/top.cc b/tests.extra/regress-thread_exit_IRQ/top.cc
index 57087ce..e1a87d7 100644
--- a/tests.extra/regress-thread_exit_IRQ/top.cc
+++ b/tests.extra/regress-thread_exit_IRQ/top.cc
@@ -1,5 +1,5 @@
 #include "helper.h"
 void __cheri_compartment("top") entry()
 {
-	asm volatile ("cmove cra, %0; cret" : : "C"(help()));
+	asm volatile("cmove cra, %0; cret" : : "C"(help()));
 }