diff --git a/c/src/lib/libbsp/arm/shared/armv7m/clock/armv7m-clock-config.c b/c/src/lib/libbsp/arm/shared/armv7m/clock/armv7m-clock-config.c
index 2e1611a85f..5ac709d10b 100644
--- a/c/src/lib/libbsp/arm/shared/armv7m/clock/armv7m-clock-config.c
+++ b/c/src/lib/libbsp/arm/shared/armv7m/clock/armv7m-clock-config.c
@@ -20,7 +20,7 @@
 #ifdef ARM_MULTILIB_ARCH_V7M
 
 /* This is defined in clockdrv_shell.h */
-void Clock_isr(rtems_irq_hdl_param arg);
+static void Clock_isr(void *arg);
 
 #define _ARMV7M_Systick_get_factor(freq) \
   ((1000000000ULL << 32) / (freq))