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diff --git a/base/win/dllmain.cc b/base/win/dllmain.cc
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-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// Windows doesn't support pthread_key_create's destr_function, and in fact
-// it's a bit tricky to get code to run when a thread exits. This is
-// cargo-cult magic from http://www.codeproject.com/threads/tls.asp.
-// We are trying to be compatible with both a LoadLibrary style invocation, as
-// well as static linking. This code only needs to be included if we use
-// LoadLibrary, but it hooks into the "standard" set of TLS callbacks that are
-// provided for static linking.
-
-// This code is deliberately written to match the style of calls seen in
-// base/threading/thread_local_storage_win.cc. Please keep the two in sync if
-// coding conventions are changed.
-
-// WARNING: Do *NOT* try to include this in the construction of the base
-// library, even though it potentially drives code in
-// base/threading/thread_local_storage_win.cc. If you do, some users will end
-// up getting duplicate definition of DllMain() in some of their later links.
-
-// Force a reference to _tls_used to make the linker create the TLS directory
-// if it's not already there (that is, even if __declspec(thread) is not used).
-// Force a reference to p_thread_callback_dllmain_typical_entry to prevent whole
-// program optimization from discarding the variables.
-
-#include <windows.h>
-
-#include "base/compiler_specific.h"
-#include "base/win/win_util.h"
-
-// Indicate if another service is scanning the callbacks. When this becomes
-// set to true, then DllMain() will stop supporting the callback service. This
-// value is set to true the first time any of our callbacks are called, as that
-// shows that some other service is handling callbacks.
-static bool linker_notifications_are_active = false;
-
-// This will be our mostly no-op callback that we'll list. We won't
-// deliberately call it, and if it is called, that means we don't need to do any
-// of the callbacks anymore. We expect such a call to arrive via a
-// THREAD_ATTACH message, long before we'd have to perform our THREAD_DETACH
-// callbacks.
-static void NTAPI on_callback(PVOID h, DWORD reason, PVOID reserved);
-
-#ifdef _WIN64
-
-#pragma comment(linker, "/INCLUDE:_tls_used")
-#pragma comment(linker, "/INCLUDE:p_thread_callback_dllmain_typical_entry")
-
-#else // _WIN64
-
-#pragma comment(linker, "/INCLUDE:__tls_used")
-#pragma comment(linker, "/INCLUDE:_p_thread_callback_dllmain_typical_entry")
-
-#endif // _WIN64
-
-// Explicitly depend on VC\crt\src\tlssup.c variables
-// to bracket the list of TLS callbacks.
-extern "C" PIMAGE_TLS_CALLBACK __xl_a, __xl_z;
-
-// extern "C" suppresses C++ name mangling so we know the symbol names for the
-// linker /INCLUDE:symbol pragmas above.
-extern "C" {
-#ifdef _WIN64
-
-// .CRT section is merged with .rdata on x64 so it must be constant data.
-#pragma data_seg(push, old_seg)
-// Use a typical possible name in the .CRT$XL? list of segments.
-#pragma const_seg(".CRT$XLB")
-// When defining a const variable, it must have external linkage to be sure the
-// linker doesn't discard it.
-extern const PIMAGE_TLS_CALLBACK p_thread_callback_dllmain_typical_entry;
-const PIMAGE_TLS_CALLBACK p_thread_callback_dllmain_typical_entry = on_callback;
-#pragma data_seg(pop, old_seg)
-
-#else // _WIN64
-
-#pragma data_seg(push, old_seg)
-// Use a typical possible name in the .CRT$XL? list of segments.
-#pragma data_seg(".CRT$XLB")
-PIMAGE_TLS_CALLBACK p_thread_callback_dllmain_typical_entry = on_callback;
-#pragma data_seg(pop, old_seg)
-
-#endif // _WIN64
-} // extern "C"
-
-// Custom crash code to get a unique entry in crash reports.
-NOINLINE static void CrashOnProcessDetach() {
- *static_cast<volatile int*>(0) = 0x356;
-}
-
-// Make DllMain call the listed callbacks. This way any third parties that are
-// linked in will also be called.
-BOOL WINAPI DllMain(PVOID h, DWORD reason, PVOID reserved) {
- if (DLL_PROCESS_DETACH == reason && base::win::ShouldCrashOnProcessDetach())
- CrashOnProcessDetach();
-
- if (DLL_THREAD_DETACH != reason && DLL_PROCESS_DETACH != reason)
- return true; // We won't service THREAD_ATTACH calls.
-
- if (linker_notifications_are_active)
- return true; // Some other service is doing this work.
-
- for (PIMAGE_TLS_CALLBACK* it = &__xl_a; it < &__xl_z; ++it) {
- if (*it == NULL || *it == on_callback)
- continue; // Don't bother to call our own callback.
- (*it)(h, reason, reserved);
- }
- return true;
-}
-
-static void NTAPI on_callback(PVOID h, DWORD reason, PVOID reserved) {
- // Do nothing. We were just a place holder in the list used to test that we
- // call all items.
- // If we are called, it means that some other system is scanning the callbacks
- // and we don't need to do so in DllMain().
- linker_notifications_are_active = true;
- // Note: If some other routine some how plays this same game... we could both
- // decide not to do the scanning <sigh>, but this trick should suppress
- // duplicate calls on Vista, where the runtime takes care of the callbacks,
- // and allow us to do the callbacks on XP, where we are currently devoid of
- // callbacks (due to an explicit LoadLibrary call).
-}