diff --git a/sys/libkern/strtoq.c b/sys/libkern/strtoq.c
index ea4e7edbc02e..d85505689090 100644
--- a/sys/libkern/strtoq.c
+++ b/sys/libkern/strtoq.c
@@ -125,6 +125,6 @@ strtoq(const char *nptr, char **endptr, int base)
 	} else if (neg)
 		acc = -acc;
 	if (endptr != 0)
-		*((const char **)endptr) = any ? s - 1 : nptr;
+		*endptr = __DECONST(char *, any ? s - 1 : nptr);
 	return (acc);
 }
diff --git a/sys/libkern/strtoul.c b/sys/libkern/strtoul.c
index 5c97ca912579..f7399dc13ef6 100644
--- a/sys/libkern/strtoul.c
+++ b/sys/libkern/strtoul.c
@@ -103,6 +103,6 @@ strtoul(nptr, endptr, base)
 	} else if (neg)
 		acc = -acc;
 	if (endptr != 0)
-		*((const char **)endptr) = any ? s - 1 : nptr;
+		*endptr = __DECONST(char *, any ? s - 1 : nptr);
 	return (acc);
 }
diff --git a/sys/libkern/strtouq.c b/sys/libkern/strtouq.c
index 5877396023fd..f8303a0d2be8 100644
--- a/sys/libkern/strtouq.c
+++ b/sys/libkern/strtouq.c
@@ -102,6 +102,6 @@ strtouq(const char *nptr, char **endptr, int base)
 	} else if (neg)
 		acc = -acc;
 	if (endptr != 0)
-		*((const char **)endptr) = any ? s - 1 : nptr;
+		*endptr = __DECONST(char *, any ? s - 1 : nptr);
 	return (acc);
 }