diff --git a/lib/libc/gen/sem.c b/lib/libc/gen/sem.c
index 2547eb2d16c8..fbed62a7138b 100644
--- a/lib/libc/gen/sem.c
+++ b/lib/libc/gen/sem.c
@@ -333,7 +333,7 @@ sem_post(sem_t *sem)
 }
 
 int
-sem_getvalue(sem_t *sem, int *sval)
+sem_getvalue(sem_t * __restrict sem, int * __restrict sval)
 {
 	int	retval;
 
diff --git a/lib/libc/gen/sem_getvalue.3 b/lib/libc/gen/sem_getvalue.3
index d1cc3a4d3296..6ccff5c5121f 100644
--- a/lib/libc/gen/sem_getvalue.3
+++ b/lib/libc/gen/sem_getvalue.3
@@ -37,7 +37,7 @@
 .Sh SYNOPSIS
 .In semaphore.h
 .Ft int
-.Fn sem_getvalue "sem_t *sem" "int *sval"
+.Fn sem_getvalue "sem_t * restrict sem" "int * restrict sval"
 .Sh DESCRIPTION
 The
 .Fn sem_getvalue
diff --git a/lib/libc/sys/sem.c b/lib/libc/sys/sem.c
index 2547eb2d16c8..fbed62a7138b 100644
--- a/lib/libc/sys/sem.c
+++ b/lib/libc/sys/sem.c
@@ -333,7 +333,7 @@ sem_post(sem_t *sem)
 }
 
 int
-sem_getvalue(sem_t *sem, int *sval)
+sem_getvalue(sem_t * __restrict sem, int * __restrict sval)
 {
 	int	retval;
 
diff --git a/lib/libc_r/man/sem_getvalue.3 b/lib/libc_r/man/sem_getvalue.3
index d1cc3a4d3296..6ccff5c5121f 100644
--- a/lib/libc_r/man/sem_getvalue.3
+++ b/lib/libc_r/man/sem_getvalue.3
@@ -37,7 +37,7 @@
 .Sh SYNOPSIS
 .In semaphore.h
 .Ft int
-.Fn sem_getvalue "sem_t *sem" "int *sval"
+.Fn sem_getvalue "sem_t * restrict sem" "int * restrict sval"
 .Sh DESCRIPTION
 The
 .Fn sem_getvalue