diff --git a/arch/sim/src/up_internal.h b/arch/sim/src/up_internal.h
index 28eaf217fc4..d344bdbb43c 100644
--- a/arch/sim/src/up_internal.h
+++ b/arch/sim/src/up_internal.h
@@ -224,8 +224,8 @@ int sim_cpustart(int cpu, main_t idletask);
 /* up_smpsignal.c *********************************************************/
 
 #ifdef CONFIG_SMP
-void sim_cpupause(int cpu, FAR volatile spinlock_t *wait,
-                  FAR volatile unsigned char *paused);
+void sim_cpu_pause(int cpu, FAR volatile spinlock_t *wait,
+                   FAR volatile unsigned char *paused);
 #endif
 
 /* up_tickless.c **********************************************************/
diff --git a/arch/sim/src/up_simsmp.c b/arch/sim/src/up_simsmp.c
index 9650022d9ce..df8ac26130d 100644
--- a/arch/sim/src/up_simsmp.c
+++ b/arch/sim/src/up_simsmp.c
@@ -37,6 +37,8 @@
  * Included Files
  ****************************************************************************/
 
+#define _GNU_SOURCE 1
+
 #include <stdint.h>
 #include <pthread.h>
 #include <semaphore.h>
@@ -84,8 +86,8 @@ static volatile spinlock_t    g_sim_cpuwait[CONFIG_SMP_NCPUS];
  * NuttX domain function prototypes
  ****************************************************************************/
 
-void sim_cpupause(int cpu, volatile spinlock_t *wait,
-                  volatile unsigned char *paused);
+void sim_cpu_pause(int cpu, volatile spinlock_t *wait,
+                   volatile unsigned char *paused);
 
 /****************************************************************************
  * Private Functions
@@ -170,7 +172,7 @@ static void sim_handle_signal(int signo, siginfo_t *info, void *context)
 
   /* We need to perform the actual tasking operations in the NuttX domain */
 
-  sim_cpupause(cpu, &g_sim_cpuwait[cpu], &g_sim_cpupaused[cpu]);
+  sim_cpu_pause(cpu, &g_sim_cpuwait[cpu], &g_sim_cpupaused[cpu]);
 }
 
 /****************************************************************************
diff --git a/arch/sim/src/up_smpsignal.c b/arch/sim/src/up_smpsignal.c
index f1e7aa8d1ba..e12a933d931 100644
--- a/arch/sim/src/up_smpsignal.c
+++ b/arch/sim/src/up_smpsignal.c
@@ -52,7 +52,7 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: sim_cpupause
+ * Name: sim_cpu_pause
  *
  * Description:
  *   This is the SIGUSR1 signal handling logic.  It implements the core
@@ -70,8 +70,8 @@
  *
  ****************************************************************************/
 
-void sim_cpupause(int cpu, volatile spinlock_t *wait,
-                  volatile unsigned char *paused)
+void sim_cpu_pause(int cpu, volatile spinlock_t *wait,
+                   volatile unsigned char *paused)
 {
   struct tcb_s *rtcb = current_task(cpu);