diff --git a/libc/Android.bp b/libc/Android.bp
index 3877145..cda9eaa 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -1984,14 +1984,6 @@
     srcs: ["arch-common/bionic/crtbegin.c"],
 
     arch: {
-        arm64: {
-            srcs: [
-                "arch-arm64/bionic/crtbegin.c",
-            ],
-            exclude_srcs: [
-                "arch-common/bionic/crtbegin.c",
-            ],
-        },
         mips: {
             srcs: [
                 "arch-mips/bionic/crtbegin.c",
@@ -2029,14 +2021,6 @@
     srcs: ["arch-common/bionic/crtbegin.c"],
 
     arch: {
-        arm64: {
-            srcs: [
-                "arch-arm64/bionic/crtbegin.c",
-            ],
-            exclude_srcs: [
-                "arch-common/bionic/crtbegin.c",
-            ],
-        },
         mips: {
             srcs: [
                 "arch-mips/bionic/crtbegin.c",
diff --git a/libc/arch-arm/cortex-a15/bionic/__strcat_chk.S b/libc/arch-arm/cortex-a15/bionic/__strcat_chk.S
index da40f6c..ca29715 100644
--- a/libc/arch-arm/cortex-a15/bionic/__strcat_chk.S
+++ b/libc/arch-arm/cortex-a15/bionic/__strcat_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of src string, then get the source of the dst string.
 // Check that the two lengths together don't exceed the threshold, then
 // do a memcpy of the data.
diff --git a/libc/arch-arm/cortex-a15/bionic/__strcpy_chk.S b/libc/arch-arm/cortex-a15/bionic/__strcpy_chk.S
index 026adcc..2679c02 100644
--- a/libc/arch-arm/cortex-a15/bionic/__strcpy_chk.S
+++ b/libc/arch-arm/cortex-a15/bionic/__strcpy_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of the source string first, then do a memcpy of the data
 // instead of a strcpy.
 ENTRY(__strcpy_chk)
diff --git a/libc/arch-arm/cortex-a15/bionic/memcpy.S b/libc/arch-arm/cortex-a15/bionic/memcpy.S
index 9407a08..7ad0093 100644
--- a/libc/arch-arm/cortex-a15/bionic/memcpy.S
+++ b/libc/arch-arm/cortex-a15/bionic/memcpy.S
@@ -59,6 +59,10 @@
         .syntax unified
         .fpu    neon
 
+        // To avoid warning about deprecated instructions, add an explicit
+        // arch. The code generated is exactly the same.
+        .arch armv7-a
+
 ENTRY(__memcpy_chk)
         cmp r2, r3
         bls memcpy
diff --git a/libc/arch-arm/cortex-a15/bionic/memset.S b/libc/arch-arm/cortex-a15/bionic/memset.S
index 2542f3f..4b4388e 100644
--- a/libc/arch-arm/cortex-a15/bionic/memset.S
+++ b/libc/arch-arm/cortex-a15/bionic/memset.S
@@ -37,6 +37,10 @@
         .fpu        neon
         .syntax     unified
 
+        // To avoid warning about deprecated instructions, add an explicit
+        // arch. The code generated is exactly the same.
+        .arch armv7-a
+
 ENTRY(__memset_chk)
         cmp         r2, r3
         bls         memset
diff --git a/libc/arch-arm/cortex-a15/bionic/strcmp.S b/libc/arch-arm/cortex-a15/bionic/strcmp.S
index 5c8914b..d8993d5 100644
--- a/libc/arch-arm/cortex-a15/bionic/strcmp.S
+++ b/libc/arch-arm/cortex-a15/bionic/strcmp.S
@@ -57,6 +57,10 @@
         .thumb_func
 #endif
 
+        // To avoid warning about deprecated instructions, add an explicit
+        // arch. The code generated is exactly the same.
+        .arch armv7-a
+
 ENTRY(strcmp)
       /* Use LDRD whenever possible.  */
 
diff --git a/libc/arch-arm/cortex-a53/bionic/__strcat_chk.S b/libc/arch-arm/cortex-a53/bionic/__strcat_chk.S
index da40f6c..ca29715 100644
--- a/libc/arch-arm/cortex-a53/bionic/__strcat_chk.S
+++ b/libc/arch-arm/cortex-a53/bionic/__strcat_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of src string, then get the source of the dst string.
 // Check that the two lengths together don't exceed the threshold, then
 // do a memcpy of the data.
diff --git a/libc/arch-arm/cortex-a53/bionic/__strcpy_chk.S b/libc/arch-arm/cortex-a53/bionic/__strcpy_chk.S
index 026adcc..2679c02 100644
--- a/libc/arch-arm/cortex-a53/bionic/__strcpy_chk.S
+++ b/libc/arch-arm/cortex-a53/bionic/__strcpy_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of the source string first, then do a memcpy of the data
 // instead of a strcpy.
 ENTRY(__strcpy_chk)
diff --git a/libc/arch-arm/cortex-a53/bionic/memcpy.S b/libc/arch-arm/cortex-a53/bionic/memcpy.S
index 9407a08..7ad0093 100644
--- a/libc/arch-arm/cortex-a53/bionic/memcpy.S
+++ b/libc/arch-arm/cortex-a53/bionic/memcpy.S
@@ -59,6 +59,10 @@
         .syntax unified
         .fpu    neon
 
+        // To avoid warning about deprecated instructions, add an explicit
+        // arch. The code generated is exactly the same.
+        .arch armv7-a
+
 ENTRY(__memcpy_chk)
         cmp r2, r3
         bls memcpy
diff --git a/libc/arch-arm/cortex-a7/bionic/__strcat_chk.S b/libc/arch-arm/cortex-a7/bionic/__strcat_chk.S
index da40f6c..ca29715 100644
--- a/libc/arch-arm/cortex-a7/bionic/__strcat_chk.S
+++ b/libc/arch-arm/cortex-a7/bionic/__strcat_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of src string, then get the source of the dst string.
 // Check that the two lengths together don't exceed the threshold, then
 // do a memcpy of the data.
diff --git a/libc/arch-arm/cortex-a7/bionic/__strcpy_chk.S b/libc/arch-arm/cortex-a7/bionic/__strcpy_chk.S
index 026adcc..2679c02 100644
--- a/libc/arch-arm/cortex-a7/bionic/__strcpy_chk.S
+++ b/libc/arch-arm/cortex-a7/bionic/__strcpy_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of the source string first, then do a memcpy of the data
 // instead of a strcpy.
 ENTRY(__strcpy_chk)
diff --git a/libc/arch-arm/cortex-a7/bionic/memcpy.S b/libc/arch-arm/cortex-a7/bionic/memcpy.S
index 9407a08..7ad0093 100644
--- a/libc/arch-arm/cortex-a7/bionic/memcpy.S
+++ b/libc/arch-arm/cortex-a7/bionic/memcpy.S
@@ -59,6 +59,10 @@
         .syntax unified
         .fpu    neon
 
+        // To avoid warning about deprecated instructions, add an explicit
+        // arch. The code generated is exactly the same.
+        .arch armv7-a
+
 ENTRY(__memcpy_chk)
         cmp r2, r3
         bls memcpy
diff --git a/libc/arch-arm/cortex-a7/bionic/memset.S b/libc/arch-arm/cortex-a7/bionic/memset.S
index e4fb1b4..72ee613 100644
--- a/libc/arch-arm/cortex-a7/bionic/memset.S
+++ b/libc/arch-arm/cortex-a7/bionic/memset.S
@@ -37,6 +37,10 @@
         .fpu        neon
         .syntax     unified
 
+        // To avoid warning about deprecated instructions, add an explicit
+        // arch. The code generated is exactly the same.
+        .arch armv7-a
+
 ENTRY(__memset_chk)
         cmp         r2, r3
         bls         memset
diff --git a/libc/arch-arm/denver/bionic/__strcat_chk.S b/libc/arch-arm/denver/bionic/__strcat_chk.S
index 9f7db59..d4f651c 100644
--- a/libc/arch-arm/denver/bionic/__strcat_chk.S
+++ b/libc/arch-arm/denver/bionic/__strcat_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of src string, then get the source of the dst string.
 // Check that the two lengths together don't exceed the threshold, then
 // do a memcpy of the data.
diff --git a/libc/arch-arm/denver/bionic/__strcpy_chk.S b/libc/arch-arm/denver/bionic/__strcpy_chk.S
index 9b7ea91..9295a00 100644
--- a/libc/arch-arm/denver/bionic/__strcpy_chk.S
+++ b/libc/arch-arm/denver/bionic/__strcpy_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of the source string first, then do a memcpy of the data
 // instead of a strcpy.
 ENTRY(__strcpy_chk)
diff --git a/libc/arch-arm/denver/bionic/memcpy.S b/libc/arch-arm/denver/bionic/memcpy.S
index d4e0fb4..743c74b 100644
--- a/libc/arch-arm/denver/bionic/memcpy.S
+++ b/libc/arch-arm/denver/bionic/memcpy.S
@@ -61,6 +61,10 @@
         .syntax unified
         .fpu    neon
 
+        // To avoid warning about deprecated instructions, add an explicit
+        // arch. The code generated is exactly the same.
+        .arch armv7-a
+
 ENTRY(__memcpy_chk)
         cmp     r2, r3
         bls     memcpy
diff --git a/libc/arch-arm/krait/bionic/__strcat_chk.S b/libc/arch-arm/krait/bionic/__strcat_chk.S
index a46ff98..32fa82d 100644
--- a/libc/arch-arm/krait/bionic/__strcat_chk.S
+++ b/libc/arch-arm/krait/bionic/__strcat_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of src string, then get the source of the dst string.
 // Check that the two lengths together don't exceed the threshold, then
 // do a memcpy of the data.
diff --git a/libc/arch-arm/krait/bionic/__strcpy_chk.S b/libc/arch-arm/krait/bionic/__strcpy_chk.S
index 9c2f66a..ca4cf7f 100644
--- a/libc/arch-arm/krait/bionic/__strcpy_chk.S
+++ b/libc/arch-arm/krait/bionic/__strcpy_chk.S
@@ -33,6 +33,10 @@
     .thumb
     .thumb_func
 
+    // To avoid warning about deprecated instructions, add an explicit
+    // arch. The code generated is exactly the same.
+    .arch armv7-a
+
 // Get the length of the source string first, then do a memcpy of the data
 // instead of a strcpy.
 ENTRY(__strcpy_chk)
diff --git a/libc/arch-arm64/bionic/crtbegin.c b/libc/arch-arm64/bionic/crtbegin.c
deleted file mode 100644
index 7e2c5d7..0000000
--- a/libc/arch-arm64/bionic/crtbegin.c
+++ /dev/null
@@ -1,70 +0,0 @@
-/*
- * Copyright (C) 2013 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 "../../bionic/libc_init_common.h"
-#include <stddef.h>
-#include <stdint.h>
-
-__attribute__ ((section (".preinit_array")))
-void (*__PREINIT_ARRAY__)(void) = (void (*)(void)) -1;
-
-__attribute__ ((section (".init_array")))
-void (*__INIT_ARRAY__)(void) = (void (*)(void)) -1;
-
-__attribute__ ((section (".fini_array")))
-void (*__FINI_ARRAY__)(void) = (void (*)(void)) -1;
-
-
-__LIBC_HIDDEN__ void do_arm64_start(void* raw_args) {
-  structors_array_t array;
-  array.preinit_array = &__PREINIT_ARRAY__;
-  array.init_array = &__INIT_ARRAY__;
-  array.fini_array = &__FINI_ARRAY__;
-  __libc_init(raw_args, NULL, &main, &array);
-}
-
-/*
- * Put the value of sp in x0 and call do_arm64_init(). The latter will then
- * then be able to access the stack as prepared by the kernel's execve system
- * call (via the first argument).
- */
-__asm__ (
-"        .text                      \n"
-"        .align  2                  \n"
-"        .global _start             \n"
-"        .hidden _start             \n"
-"        .type   _start, %function  \n"
-"_start:                            \n"
-"        add     x0, sp, xzr        \n"
-"        b       do_arm64_start   \n"
-"        .size   _start, .-_start   \n"
-);
-
-#include "../../arch-common/bionic/__dso_handle.h"
-#include "../../arch-common/bionic/atexit.h"
-#include "../../arch-common/bionic/pthread_atfork.h"
diff --git a/libc/arch-common/bionic/crtbegin.c b/libc/arch-common/bionic/crtbegin.c
index c46405c..d3a0f07 100644
--- a/libc/arch-common/bionic/crtbegin.c
+++ b/libc/arch-common/bionic/crtbegin.c
@@ -30,36 +30,42 @@
 #include <stddef.h>
 #include <stdint.h>
 
-__attribute__ ((section (".preinit_array")))
+__attribute__((__section__(".preinit_array")))
 void (*__PREINIT_ARRAY__)(void) = (void (*)(void)) -1;
 
-__attribute__ ((section (".init_array")))
+__attribute__((__section__(".init_array")))
 void (*__INIT_ARRAY__)(void) = (void (*)(void)) -1;
 
-__attribute__ ((section (".fini_array")))
+__attribute__((__section__(".fini_array")))
 void (*__FINI_ARRAY__)(void) = (void (*)(void)) -1;
 
-__LIBC_HIDDEN__
-#ifdef __i386__
-__attribute__((force_align_arg_pointer))
-#endif
-void _start() {
+static void _start_main(void* raw_args) {
   structors_array_t array;
   array.preinit_array = &__PREINIT_ARRAY__;
   array.init_array = &__INIT_ARRAY__;
   array.fini_array = &__FINI_ARRAY__;
 
-  void* raw_args = (void*) ((uintptr_t) __builtin_frame_address(0) + sizeof(void*));
-#ifdef __x86_64__
-  // 16-byte stack alignment is required by x86_64 ABI
-  asm("andq  $~15, %rsp");
-#endif
   __libc_init(raw_args, NULL, &main, &array);
 }
 
+#define PRE ".text; .global _start; .type _start,%function; _start:"
+#define POST "; .size _start, .-_start"
+
+#if defined(__aarch64__)
+__asm__(PRE "mov x0,sp; b _start_main" POST);
+#elif defined(__arm__)
+__asm__(PRE "mov r0,sp; b _start_main" POST);
+#elif defined(__i386__)
+__asm__(PRE "movl %esp,%eax; andl $~0xf,%esp; pushl %eax; calll _start_main" POST);
+#elif defined(__x86_64__)
+__asm__(PRE "movq %rsp,%rdi; andq $~0xf,%rsp; callq _start_main" POST);
+#else
+#error unsupported architecture
+#endif
+
+#undef PRE
+#undef POST
+
 #include "__dso_handle.h"
 #include "atexit.h"
 #include "pthread_atfork.h"
-#ifdef __i386__
-# include "../../arch-x86/bionic/__stack_chk_fail_local.h"
-#endif
diff --git a/libc/arch-common/bionic/crtbegin_so.c b/libc/arch-common/bionic/crtbegin_so.c
index 3754363..258a6cd 100644
--- a/libc/arch-common/bionic/crtbegin_so.c
+++ b/libc/arch-common/bionic/crtbegin_so.c
@@ -57,6 +57,3 @@
 # include "atexit.h"
 #endif
 #include "pthread_atfork.h"
-#ifdef __i386__
-# include "../../arch-x86/bionic/__stack_chk_fail_local.h"
-#endif
diff --git a/libc/arch-x86/bionic/__stack_chk_fail_local.h b/libc/arch-x86/bionic/__stack_chk_fail_local.h
deleted file mode 100644
index 0b0fd7f..0000000
--- a/libc/arch-x86/bionic/__stack_chk_fail_local.h
+++ /dev/null
@@ -1,57 +0,0 @@
-/*
- * Copyright (C) 2012 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 <sys/cdefs.h>
-
-/*
-   __stack_chk_fail routine is runtime part of stack protector compiler
-   feature. It's implemented in libc and represents die routine when stack
-   corruption is detected.
-
-   Calls are generated by compiler and injected into user functions when
-   -fstack-protector* options are used.
-
-   __stack_chk_fail_local is wrapper for __stack_chk_fail. Compiler generates
-   wrapper calls instead for PIC code only and only on IA32 for optimization
-   purpose (see gcc/config/i386/i386.c). Wrapper body is always included into
-   executable or library. This is the idea of optimization.
-
-   Glibc is doing this via libc_nonshared.a which is linked automatically
-   everytime with libc.so. In bionic we have to bring it within crtfiles
-   because libc.so is real library and not a link script like libc.so at glibc.
-
-   For x86_64 or non-PIC code compiler always generates __stack_chk_fail calls.
-*/
-
-#ifdef __i386__
-extern void __stack_chk_fail();
-
-__LIBC_HIDDEN__ void __stack_chk_fail_local() {
-  __stack_chk_fail();
-}
-#endif
diff --git a/libc/dns/include/resolv_netid.h b/libc/dns/include/resolv_netid.h
index 711792b..3b2f4da 100644
--- a/libc/dns/include/resolv_netid.h
+++ b/libc/dns/include/resolv_netid.h
@@ -86,6 +86,7 @@
  * explore_fqdn() dispatch table method, with the below function only making DNS calls.
  */
 struct hostent *android_gethostbyaddrfornetcontext(const void *, socklen_t, int, const struct android_net_context *) __used_in_netd;
+struct hostent *android_gethostbynamefornetcontext(const char *, int, const struct android_net_context *) __used_in_netd;
 int android_getaddrinfofornetcontext(const char *, const char *, const struct addrinfo *,
     const struct android_net_context *, struct addrinfo **) __used_in_netd;
 
diff --git a/libc/dns/include/resolv_private.h b/libc/dns/include/resolv_private.h
index 284270c..77b03bf 100644
--- a/libc/dns/include/resolv_private.h
+++ b/libc/dns/include/resolv_private.h
@@ -504,8 +504,8 @@
 __LIBC_HIDDEN__ int		res_getservers(res_state,
 				    union res_sockaddr_union *, int);
 
-__LIBC_HIDDEN__ void res_setnetid(res_state, unsigned);
-__LIBC_HIDDEN__ void res_setmark(res_state, unsigned);
+struct android_net_context; /* forward */
+__LIBC_HIDDEN__ void res_setnetcontext(res_state, const struct android_net_context *);
 
 // We use the OpenBSD __res_randomid...
 u_int __res_randomid(void);
diff --git a/libc/dns/net/getaddrinfo.c b/libc/dns/net/getaddrinfo.c
index 4215963..418bf6d 100644
--- a/libc/dns/net/getaddrinfo.c
+++ b/libc/dns/net/getaddrinfo.c
@@ -1981,8 +1981,7 @@
 	 * fully populate the thread private data here, but if we get down there
 	 * and have a cache hit that would be wasted, so we do the rest there on miss
 	 */
-	res_setnetid(res, netcontext->dns_netid);
-	res_setmark(res, netcontext->dns_mark);
+	res_setnetcontext(res, netcontext);
 	if (res_searchN(name, &q, res) < 0) {
 		__res_put_state(res);
 		free(buf);
diff --git a/libc/dns/net/gethnamaddr.c b/libc/dns/net/gethnamaddr.c
index 036ad1d..4e416fd 100644
--- a/libc/dns/net/gethnamaddr.c
+++ b/libc/dns/net/gethnamaddr.c
@@ -160,7 +160,7 @@
 static int _dns_gethtbyname(void *, void *, va_list);
 
 static struct hostent *gethostbyname_internal(const char *, int, res_state,
-    struct hostent *, char *, size_t, int *, unsigned, unsigned);
+    struct hostent *, char *, size_t, int *, const struct android_net_context *);
 static struct hostent* android_gethostbyaddrfornetcontext_proxy_internal(const void*, socklen_t,
     int, struct hostent *, char *, size_t, int *, const struct android_net_context *);
 
@@ -529,15 +529,15 @@
 	_DIAGASSERT(name != NULL);
 
 	if (res->options & RES_USE_INET6) {
-		*result = gethostbyname_internal(name, AF_INET6, res, hp, buf, buflen, errorp, NETID_UNSET,
-		                                 MARK_UNSET);
+		*result = gethostbyname_internal(name, AF_INET6, res, hp, buf, buflen, errorp,
+		                                 &NETCONTEXT_UNSET);
 		if (*result) {
 			__res_put_state(res);
 			return 0;
 		}
 	}
-	*result = gethostbyname_internal(name, AF_INET, res, hp, buf, buflen, errorp, NETID_UNSET,
-	                                 MARK_UNSET);
+	*result = gethostbyname_internal(name, AF_INET, res, hp, buf, buflen, errorp,
+	                                 &NETCONTEXT_UNSET);
 	__res_put_state(res);
 	if (!*result && errno == ENOSPC) {
 	  errno = ERANGE;
@@ -558,8 +558,8 @@
 		*errorp = NETDB_INTERNAL;
 		return -1;
 	}
-	*result = gethostbyname_internal(name, af, res, hp, buf, buflen, errorp, NETID_UNSET,
-	                                 MARK_UNSET);
+	*result = gethostbyname_internal(name, af, res, hp, buf, buflen, errorp,
+	                                 &NETCONTEXT_UNSET);
 	__res_put_state(res);
 	if (!*result && errno == ENOSPC) {
 		errno = ERANGE;
@@ -822,17 +822,16 @@
 // very similar in proxy-ness to android_getaddrinfo_proxy
 static struct hostent *
 gethostbyname_internal(const char *name, int af, res_state res, struct hostent *hp, char *hbuf,
-                       size_t hbuflen, int *errorp, unsigned netid, unsigned mark)
+                       size_t hbuflen, int *errorp, const struct android_net_context *netcontext)
 {
 	FILE* proxy = android_open_proxy();
 	if (proxy == NULL) {
 		// Either we're not supposed to be using the proxy or the proxy is unavailable.
-		res_setnetid(res, netid);
-		res_setmark(res, mark);
+		res_setnetcontext(res, netcontext);
 		return gethostbyname_internal_real(name, af, res, hp, hbuf, hbuflen, errorp);
 	}
 
-	netid = __netdClientDispatch.netIdForResolv(netid);
+	unsigned netid = __netdClientDispatch.netIdForResolv(netcontext->app_netid);
 
 	// This is writing to system/netd/server/DnsProxyListener.cpp and changes
 	// here need to be matched there.
@@ -1296,8 +1295,7 @@
 		free(buf);
 		return NS_NOTFOUND;
 	}
-	res_setnetid(res, netcontext->dns_netid);
-	res_setmark(res, netcontext->dns_mark);
+	res_setnetcontext(res, netcontext);
 	n = res_nquery(res, qbuf, C_IN, T_PTR, buf->buf, (int)sizeof(buf->buf));
 	if (n < 0) {
 		free(buf);
@@ -1611,13 +1609,21 @@
 struct hostent *
 android_gethostbynamefornet(const char *name, int af, unsigned netid, unsigned mark)
 {
+	const struct android_net_context netcontext = make_context(netid, mark);
+	return android_gethostbynamefornetcontext(name, af, &netcontext);
+}
+
+struct hostent *
+android_gethostbynamefornetcontext(const char *name, int af,
+	const struct android_net_context *netcontext)
+{
 	struct hostent *hp;
 	res_state res = __res_get_state();
 	if (res == NULL)
 		return NULL;
 	res_static rs = __res_get_static(); /* Use res_static to provide thread-safety. */
 	hp = gethostbyname_internal(name, af, res, &rs->host, rs->hostbuf, sizeof(rs->hostbuf),
-	                            &h_errno, netid, mark);
+	                            &h_errno, netcontext);
 	__res_put_state(res);
 	return hp;
 }
diff --git a/libc/dns/resolv/res_init.c b/libc/dns/resolv/res_init.c
index b9fc131..302a62b 100644
--- a/libc/dns/resolv/res_init.c
+++ b/libc/dns/resolv/res_init.c
@@ -768,17 +768,12 @@
 }
 
 #ifdef ANDROID_CHANGES
-void res_setnetid(res_state statp, unsigned netid)
+void res_setnetcontext(res_state statp, const struct android_net_context *netcontext)
 {
 	if (statp != NULL) {
-		statp->netid = netid;
-	}
-}
-
-void res_setmark(res_state statp, unsigned mark)
-{
-	if (statp != NULL) {
-		statp->_mark = mark;
+		statp->netid = netcontext->dns_netid;
+		statp->_mark = netcontext->dns_mark;
+		statp->qhook = netcontext->qhook;
 	}
 }
 
diff --git a/libc/include/bits/posix_limits.h b/libc/include/bits/posix_limits.h
index db09bd7..cfc46f5 100644
--- a/libc/include/bits/posix_limits.h
+++ b/libc/include/bits/posix_limits.h
@@ -99,7 +99,7 @@
 #define _POSIX_THREAD_PRIORITY_SCHEDULING 200809L
 #define _POSIX_THREAD_PRIO_INHERIT -1  /* not implemented */
 #define _POSIX_THREAD_PRIO_PROTECT -1  /* not implemented */
-#define _POSIX_THREAD_PROCESS_SHARED  -1  /* not implemented */
+#define _POSIX_THREAD_PROCESS_SHARED  200809L  /* PTHREAD_PROCESS_SHARED supported. */
 #define _POSIX_THREAD_ROBUST_PRIO_INHERIT -1  /* not implemented */
 #define _POSIX_THREAD_ROBUST_PRIO_PROTECT -1  /* not implemented */
 #define _POSIX_THREAD_SAFE_FUNCTIONS 200809L
diff --git a/libc/include/sys/epoll.h b/libc/include/sys/epoll.h
index b7fdd4d..5e92fdc 100644
--- a/libc/include/sys/epoll.h
+++ b/libc/include/sys/epoll.h
@@ -75,6 +75,22 @@
 
 int epoll_create(int);
 int epoll_create1(int) __INTRODUCED_IN(21);
+
+/*
+ * Some third-party code uses the existence of EPOLL_CLOEXEC to detect the
+ * availability of epoll_create1. This is not correct, since having up-to-date
+ * UAPI headers says nothing about the C library, but for the time being we
+ * don't want to harm adoption to the unified headers. We'll undef EPOLL_CLOEXEC
+ * if we don't have epoll_create1 for the time being, and maybe revisit this
+ * later.
+ *
+ * https://github.com/android-ndk/ndk/issues/302
+ * https://github.com/android-ndk/ndk/issues/394
+ */
+#if __ANDROID_API__ < __ANDROID_API_L__ && defined(EPOLL_CLOEXEC)
+#undef EPOLL_CLOEXEC
+#endif
+
 int epoll_ctl(int, int, int, struct epoll_event*);
 int epoll_wait(int, struct epoll_event*, int, int);
 int epoll_pwait(int, struct epoll_event*, int, int, const sigset_t*) __INTRODUCED_IN(21);
diff --git a/libc/include/sys/inotify.h b/libc/include/sys/inotify.h
index 2e99144..98f7198 100644
--- a/libc/include/sys/inotify.h
+++ b/libc/include/sys/inotify.h
@@ -37,8 +37,21 @@
 
 __BEGIN_DECLS
 
+/*
+ * Some third-party code uses the existence of IN_CLOEXEC/IN_NONBLOCK to detect
+ * the availability of inotify_init1. This is not correct, since
+ * `syscall(__NR_inotify_init1, IN_CLOEXEC)` is still valid even if the C
+ * library doesn't have that function, but for the time being we don't want to
+ * harm adoption to the unified headers. We'll avoid defining IN_CLOEXEC and
+ * IN_NONBLOCK if we don't have inotify_init1 for the time being, and maybe
+ * revisit this later.
+ *
+ * https://github.com/android-ndk/ndk/issues/394
+ */
+#if __ANDROID_API__ >= __ANDROID_API_L__
 #define IN_CLOEXEC O_CLOEXEC
 #define IN_NONBLOCK O_NONBLOCK
+#endif
 
 int inotify_init(void);
 int inotify_init1(int) __INTRODUCED_IN(21);
diff --git a/libc/libc.arm.map b/libc/libc.arm.map
index a74027a..b32f769 100644
--- a/libc/libc.arm.map
+++ b/libc/libc.arm.map
@@ -1496,6 +1496,7 @@
     android_gethostbyaddrfornet;
     android_gethostbyaddrfornetcontext;
     android_gethostbynamefornet;
+    android_gethostbynamefornetcontext;
     arc4random_addrandom; # arm x86 mips
     arc4random_stir; # arm x86 mips
     atexit; # arm
diff --git a/libc/libc.arm64.map b/libc/libc.arm64.map
index 34d3429..afcf8bb 100644
--- a/libc/libc.arm64.map
+++ b/libc/libc.arm64.map
@@ -1244,6 +1244,7 @@
     android_gethostbyaddrfornet;
     android_gethostbyaddrfornetcontext;
     android_gethostbynamefornet;
+    android_gethostbynamefornetcontext;
     free_malloc_leak_info;
     get_malloc_leak_info;
     gMallocLeakZygoteChild;
diff --git a/libc/libc.map.txt b/libc/libc.map.txt
index 90929f5..f05e7eb 100644
--- a/libc/libc.map.txt
+++ b/libc/libc.map.txt
@@ -1522,6 +1522,7 @@
     android_gethostbyaddrfornet;
     android_gethostbyaddrfornetcontext;
     android_gethostbynamefornet;
+    android_gethostbynamefornetcontext;
     arc4random_addrandom; # arm x86 mips
     arc4random_stir; # arm x86 mips
     atexit; # arm
diff --git a/libc/libc.mips.map b/libc/libc.mips.map
index aac876d..a472214 100644
--- a/libc/libc.mips.map
+++ b/libc/libc.mips.map
@@ -1339,6 +1339,7 @@
     android_gethostbyaddrfornet;
     android_gethostbyaddrfornetcontext;
     android_gethostbynamefornet;
+    android_gethostbynamefornetcontext;
     arc4random_addrandom; # arm x86 mips
     arc4random_stir; # arm x86 mips
     bcopy; # arm x86 mips
diff --git a/libc/libc.mips64.map b/libc/libc.mips64.map
index 34d3429..afcf8bb 100644
--- a/libc/libc.mips64.map
+++ b/libc/libc.mips64.map
@@ -1244,6 +1244,7 @@
     android_gethostbyaddrfornet;
     android_gethostbyaddrfornetcontext;
     android_gethostbynamefornet;
+    android_gethostbynamefornetcontext;
     free_malloc_leak_info;
     get_malloc_leak_info;
     gMallocLeakZygoteChild;
diff --git a/libc/libc.x86.map b/libc/libc.x86.map
index 682f2c4..27a597f 100644
--- a/libc/libc.x86.map
+++ b/libc/libc.x86.map
@@ -1338,6 +1338,7 @@
     android_gethostbyaddrfornet;
     android_gethostbyaddrfornetcontext;
     android_gethostbynamefornet;
+    android_gethostbynamefornetcontext;
     arc4random_addrandom; # arm x86 mips
     arc4random_stir; # arm x86 mips
     bcopy; # arm x86 mips
diff --git a/libc/libc.x86_64.map b/libc/libc.x86_64.map
index 34d3429..afcf8bb 100644
--- a/libc/libc.x86_64.map
+++ b/libc/libc.x86_64.map
@@ -1244,6 +1244,7 @@
     android_gethostbyaddrfornet;
     android_gethostbyaddrfornetcontext;
     android_gethostbynamefornet;
+    android_gethostbynamefornetcontext;
     free_malloc_leak_info;
     get_malloc_leak_info;
     gMallocLeakZygoteChild;
diff --git a/linker/arch/x86/begin.c b/linker/arch/x86/begin.c
index 051a16a..a734f25 100644
--- a/linker/arch/x86/begin.c
+++ b/linker/arch/x86/begin.c
@@ -48,9 +48,3 @@
 
   /* Unreachable */
 }
-
-/* Since linker has its own version of crtbegin (this file) it should have */
-/* own version of __stack_chk_fail_local for the case when it's built with */
-/* stack protector feature */
-
-#include "arch-x86/bionic/__stack_chk_fail_local.h"
diff --git a/tests/libs/Android.build.dlext_testzip.mk b/tests/libs/Android.build.dlext_testzip.mk
index 0220ae2..4b6d099 100644
--- a/tests/libs/Android.build.dlext_testzip.mk
+++ b/tests/libs/Android.build.dlext_testzip.mk
@@ -22,7 +22,7 @@
 
 include $(CLEAR_VARS)
 
-LOCAL_MODULE_CLASS := ETC
+LOCAL_MODULE_CLASS := NATIVE_TESTS
 LOCAL_MODULE := libdlext_test_zip_zipaligned
 LOCAL_MODULE_SUFFIX := .zip
 LOCAL_MODULE_PATH := $($(bionic_2nd_arch_prefix)TARGET_OUT_DATA_NATIVE_TESTS)/bionic-loader-test-libs/libdlext_test_zip
@@ -44,7 +44,7 @@
 
 include $(CLEAR_VARS)
 
-LOCAL_MODULE_CLASS := ETC
+LOCAL_MODULE_CLASS := NATIVE_TESTS
 LOCAL_MODULE := libdlext_test_runpath_zip_zipaligned
 LOCAL_MODULE_SUFFIX := .zip
 LOCAL_MODULE_PATH := $($(bionic_2nd_arch_prefix)TARGET_OUT_DATA_NATIVE_TESTS)/bionic-loader-test-libs/libdlext_test_runpath_zip
diff --git a/tests/unistd_test.cpp b/tests/unistd_test.cpp
index 9eae06e..109b92c 100644
--- a/tests/unistd_test.cpp
+++ b/tests/unistd_test.cpp
@@ -742,6 +742,7 @@
   EXPECT_EQ(_POSIX_VERSION, _POSIX_THREAD_PRIORITY_SCHEDULING);
   EXPECT_EQ(-1, _POSIX_THREAD_PRIO_INHERIT);
   EXPECT_EQ(-1, _POSIX_THREAD_PRIO_PROTECT);
+  EXPECT_EQ(_POSIX_VERSION, _POSIX_THREAD_PROCESS_SHARED);
   EXPECT_EQ(-1, _POSIX_THREAD_ROBUST_PRIO_PROTECT);
   EXPECT_EQ(_POSIX_VERSION, _POSIX_THREAD_SAFE_FUNCTIONS);
   EXPECT_EQ(-1, _POSIX_THREAD_SPORADIC_SERVER);
@@ -781,7 +782,6 @@
   EXPECT_EQ(-1, _POSIX_PRIORITIZED_IO);
   EXPECT_EQ(-1, _POSIX_SHARED_MEMORY_OBJECTS);
   EXPECT_EQ(-1, _POSIX_SPAWN);
-  EXPECT_EQ(-1, _POSIX_THREAD_PROCESS_SHARED);
   EXPECT_EQ(-1, _POSIX_THREAD_ROBUST_PRIO_INHERIT);
 
   EXPECT_EQ(-1, _POSIX2_VERSION);
@@ -908,6 +908,7 @@
   VERIFY_SYSCONF_UNSUPPORTED(_SC_SPORADIC_SERVER);
   VERIFY_SYSCONF_POSITIVE(_SC_SYMLOOP_MAX);
   VERIFY_SYSCONF_POSIX_VERSION(_SC_THREAD_CPUTIME);
+  VERIFY_SYSCONF_POSIX_VERSION(_SC_THREAD_PROCESS_SHARED);
   VERIFY_SYSCONF_UNSUPPORTED(_SC_THREAD_SPORADIC_SERVER);
   VERIFY_SYSCONF_POSIX_VERSION(_SC_TIMEOUTS);
   VERIFY_SYSCONF_UNSUPPORTED(_SC_TRACE);
@@ -944,7 +945,6 @@
   VERIFY_SYSCONF_UNSUPPORTED(_SC_PRIORITIZED_IO);
   VERIFY_SYSCONF_UNSUPPORTED(_SC_SHARED_MEMORY_OBJECTS);
   VERIFY_SYSCONF_UNSUPPORTED(_SC_SPAWN);
-  VERIFY_SYSCONF_UNSUPPORTED(_SC_THREAD_PROCESS_SHARED);
   VERIFY_SYSCONF_UNSUPPORTED(_SC_THREAD_ROBUST_PRIO_INHERIT);
   VERIFY_SYSCONF_UNSUPPORTED(_SC_THREAD_ROBUST_PRIO_PROTECT);