Move exit.c from stdlib to bionic subdirectory.

Test: make

Change-Id: I2182d5a7c97abc0335e88d2d9dd9f77bc7e7f633
diff --git a/libc/Android.bp b/libc/Android.bp
index 4e5ae75..c3afa3a 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -4,6 +4,7 @@
     "async_safe/async_safe_log.cpp",
     "bionic/ether_aton.c",
     "bionic/ether_ntoa.c",
+    "bionic/exit.cpp",
     "bionic/fts.c",
     "bionic/initgroups.c",
     "bionic/isatty.c",
@@ -17,7 +18,6 @@
     "stdio/stdio_ext.cpp",
     "stdio/vfscanf.cpp",
     "stdio/vfwscanf.c",
-    "stdlib/exit.c",
 ]
 
 // off64_t/time64_t support on LP32.
diff --git a/libc/bionic/exit.cpp b/libc/bionic/exit.cpp
new file mode 100644
index 0000000..a5aed78
--- /dev/null
+++ b/libc/bionic/exit.cpp
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "private/bionic_defs.h"
+
+extern "C" void __cxa_finalize(void* dso_handle);
+extern "C" void __cxa_thread_finalize();
+
+__BIONIC_WEAK_FOR_NATIVE_BRIDGE
+void exit(int status) {
+  __cxa_thread_finalize();
+  __cxa_finalize(nullptr);
+  _exit(status);
+}
diff --git a/libc/stdlib/exit.c b/libc/stdlib/exit.c
deleted file mode 100644
index e301a2a..0000000
--- a/libc/stdlib/exit.c
+++ /dev/null
@@ -1,42 +0,0 @@
-/*-
- * Copyright (c) 1990 The Regents of the University of California.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <unistd.h>
-
-#include "private/bionic_defs.h"
-
-extern void __cxa_finalize(void* dso_handle);
-extern void __cxa_thread_finalize();
-
-__BIONIC_WEAK_FOR_NATIVE_BRIDGE
-void exit(int status) {
-  __cxa_thread_finalize();
-  __cxa_finalize(NULL);
-  _exit(status);
-}