diff --git a/sys/compat/freebsd32/freebsd32_misc.c b/sys/compat/freebsd32/freebsd32_misc.c
index f0fde2b3c14..1d60ed4de39 100644
--- a/sys/compat/freebsd32/freebsd32_misc.c
+++ b/sys/compat/freebsd32/freebsd32_misc.c
@@ -2208,7 +2208,7 @@ freebsd32_thr_suspend(struct thread *td, struct freebsd32_thr_suspend_args *uap)
 }
 
 void
-siginfo_to_siginfo32(siginfo_t *src, struct siginfo32 *dst)
+siginfo_to_siginfo32(const siginfo_t *src, struct siginfo32 *dst)
 {
 	bzero(dst, sizeof(*dst));
 	dst->si_signo = src->si_signo;
diff --git a/sys/compat/freebsd32/freebsd32_signal.h b/sys/compat/freebsd32/freebsd32_signal.h
index ba0922a176b..2669581bf75 100644
--- a/sys/compat/freebsd32/freebsd32_signal.h
+++ b/sys/compat/freebsd32/freebsd32_signal.h
@@ -96,6 +96,6 @@ struct sigevent32 {
 	} _sigev_un;
 };
 
-void siginfo_to_siginfo32(siginfo_t *src, struct siginfo32 *dst);
+void siginfo_to_siginfo32(const siginfo_t *src, struct siginfo32 *dst);
 
 #endif /* !_COMPAT_FREEBSD32_SIGNAL_H_ */