Index: lib/libc/gen/pthread_atfork.c
===================================================================
RCS file: /cvsroot/src/lib/libc/gen/pthread_atfork.c,v
retrieving revision 1.10
diff -u -r1.10 pthread_atfork.c
--- lib/libc/gen/pthread_atfork.c	20 Jan 2015 18:31:25 -0000	1.10
+++ lib/libc/gen/pthread_atfork.c	1 Feb 2020 11:40:28 -0000
@@ -36,10 +36,12 @@
 
 #include "namespace.h"
 
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/queue.h>
 #include <errno.h>
 #include <stdlib.h>
 #include <unistd.h>
-#include <sys/queue.h>
 #include "reentrant.h"
 
 #ifdef __weak_alias
@@ -73,11 +75,15 @@
 static struct atfork_callback *
 af_alloc(void)
 {
+	void *arena;
 
 	if (atfork_builtin.fn == NULL)
 		return &atfork_builtin;
 
-	return malloc(sizeof(atfork_builtin));
+	arena = mmap(NULL, sizeof(atfork_builtin), PROT_READ|PROT_WRITE, MAP_ANON, -1, 0);
+	if (arena == MAP_FAILED)
+		return NULL;
+	return arena;
 }
 
 static void
@@ -85,7 +91,7 @@
 {
 
 	if (af != &atfork_builtin)
-		free(af);
+		munmap(af, sizeof(atfork_builtin));
 }
 
 int
Index: lib/libpthread/pthread_mutex.c
===================================================================
RCS file: /cvsroot/src/lib/libpthread/pthread_mutex.c,v
retrieving revision 1.72
diff -u -r1.72 pthread_mutex.c
--- lib/libpthread/pthread_mutex.c	31 Jan 2020 17:52:14 -0000	1.72
+++ lib/libpthread/pthread_mutex.c	1 Feb 2020 11:40:30 -0000
@@ -122,7 +122,7 @@
 {
 	uintptr_t type, proto, val, ceil;
 
-#if 0
+#if 1
 	/*
 	 * Always initialize the mutex structure, maybe be used later
 	 * and the cost should be minimal.
@@ -619,7 +619,7 @@
 int
 pthread_mutexattr_init(pthread_mutexattr_t *attr)
 {
-#if 0
+#if 1
 	if (__predict_false(__uselibcstub))
 		return __libc_mutexattr_init_stub(attr);
 #endif