Change the CRT initialization to create a new heap for Chrome.dll.

base/allocator/allocator_shim_override_ucrt_symbols_win.h

 // Copyright 2016 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.
 
 // This header defines symbols to override the same functions in the Visual C++
 // CRT implementation.
 
 #ifdef BASE_ALLOCATOR_ALLOCATOR_SHIM_OVERRIDE_UCRT_SYMBOLS_WIN_H_
 #error This header is meant to be included only once by allocator_shim.cc
 #endif
@@ skipping 45 matching lines @@
 }
 
 __declspec(restrict) void* realloc(void* ptr, size_t size) {
   return ShimRealloc(ptr, size);
 }
 
 __declspec(restrict) void* calloc(size_t n, size_t size) {
   return ShimCalloc(n, size);
 }
 
+// The symbols
+//   * __acrt_heap
+//   * __acrt_initialize_heap
+//   * __acrt_uninitialize_heap
+//   * _get_heap_handle
+// must be overridden all or none, as they are otherwise supplied
+// by heap_handle.obj in the ucrt.lib file.
+HANDLE __acrt_heap = nullptr;
+
+bool __acrt_initialize_heap() {
+  __acrt_heap = ::HeapCreate(0, 0, 0);

[Will Harris, 2016/12/06 19:46:35]

do these flags match the process heap?

[Sigurður Ásgeirsson, 2016/12/06 20:28:15]

I believe so, the only flags documented are 

HEAP_CREATE_ENABLE_EXECUTE
HEAP_GENERATE_EXCEPTIONS
HEAP_NO_SERIALIZE

We still have the HeapSetInformation calls in base to set the per-process heap
corruption termination policy.

[Will Harris, 2016/12/06 21:33:09]

is HeapSetInformation called on this heap as well?

+  return true;
+}
+
+bool __acrt_uninitialize_heap() {
+  ::HeapDestroy(__acrt_heap);
+  __acrt_heap = nullptr;
+  return true;
+}
+
+intptr_t _get_heap_handle(void) {
+  return reinterpret_cast<intptr_t>(__acrt_heap);
+}
+
 // The default dispatch translation unit has to define also the following
 // symbols (unless they are ultimately routed to the system symbols):
 //   void malloc_stats(void);
 //   int mallopt(int, int);
 //   struct mallinfo mallinfo(void);
 //   size_t malloc_size(void*);
 //   size_t malloc_usable_size(const void*);
 
 }  // extern "C"