Hide __atexit and remove __atexit_invalid.

Bug: 11156955
Change-Id: I8c72edee8ecb92b75a282384277253bae19f7455
diff --git a/libc/stdlib/atexit.c b/libc/stdlib/atexit.c
index c607206..05f2faa 100644
--- a/libc/stdlib/atexit.c
+++ b/libc/stdlib/atexit.c
@@ -37,7 +37,6 @@
 #include "atexit.h"
 #include "private/thread_private.h"
 
-int __atexit_invalid = 1;
 struct atexit *__atexit;
 
 /*
@@ -131,8 +130,6 @@
 		    sizeof(p->fns[0]);
 		p->next = __atexit;
 		__atexit = p;
-		if (__atexit_invalid)
-			__atexit_invalid = 0;
 	}
 	fnp = &p->fns[p->ind++];
 	fnp->cxa_func = func;
@@ -159,8 +156,6 @@
 	int n, pgsize = getpagesize(), original_ind;
 	static int call_depth;
 
-	if (__atexit_invalid)
-		return;
 	_ATEXIT_LOCK();
 	call_depth++;
 
diff --git a/libc/stdlib/atexit.h b/libc/stdlib/atexit.h
index 2e88ad6..b530ade 100644
--- a/libc/stdlib/atexit.h
+++ b/libc/stdlib/atexit.h
@@ -45,8 +45,7 @@
 
 __BEGIN_DECLS
 
-extern int __atexit_invalid;
-extern struct atexit *__atexit;		/* points to head of LIFO stack */
+__LIBC_HIDDEN__ extern struct atexit *__atexit;		/* points to head of LIFO stack */
 
 int	__cxa_atexit(void (*)(void *), void *, void *);
 void	__cxa_finalize(void *);