musl - musl - an implementation of the standard library for Linux-based systems

diff --git a/src/internal/libc.h b/src/internal/libc.h
index 703d9853..5ab4e679 100644
--- a/src/internal/libc.h
+++ b/src/internal/libc.h

@@ -46,10 +46,10 @@ extern struct __libc *__libc_loc(void) __attribute__((const));

/* Designed to avoid any overhead in non-threaded processes */

-void __lock(volatile int *);

-void __unlock(volatile int *);

-int __lockfile(FILE *);

-void __unlockfile(FILE *);

+void __lock(volatile int *) ATTR_LIBC_VISIBILITY;

+void __unlock(volatile int *) ATTR_LIBC_VISIBILITY;

+int __lockfile(FILE *) ATTR_LIBC_VISIBILITY;

+void __unlockfile(FILE *) ATTR_LIBC_VISIBILITY;

#define LOCK(x) (libc.threads_minus_1 ? (__lock(x),1) : ((void)(x),1))

#define UNLOCK(x) (libc.threads_minus_1 ? (__unlock(x),1) : ((void)(x),1))