Copy dbghelp.dll to output directory

build/vs_toolchain.py

 #!/usr/bin/env python
 # Copyright 2014 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.
 
 import glob
 import json
 import os
 import pipes
 import platform
@@ skipping 288 matching lines @@
   vs_runtime_dll_dirs = SetEnvironmentAndGetRuntimeDllDirs()
   if not vs_runtime_dll_dirs:
     return
 
   x64_runtime, x86_runtime = vs_runtime_dll_dirs
   runtime_dir = x64_runtime if target_cpu == 'x64' else x86_runtime
   _CopyRuntime(target_dir, runtime_dir, target_cpu, debug=False)
   if configuration == 'Debug':
     _CopyRuntime(target_dir, runtime_dir, target_cpu, debug=True)
 
+  _CopyDebugger(target_dir, target_cpu)
+
+
+def _CopyDebugger(target_dir, target_cpu):
+  """Copy dbghelp.dll into the requested directory as needed.
+
+  target_cpu is one of 'x86' or 'x64'.
+
+  dbghelp.dll is used when Chrome needs to symbolize stacks. Copying this file
+  from the SDK directory avoids using the system copy of dbghelp.dll which then
+  ensures compatibility with recent debug information formats, such as VS
+  2017 /debug:fastlink PDBs.
+  """
+  win_sdk_dir = SetEnvironmentAndGetSDKDir()
+  if not win_sdk_dir:
+    return
+
+  debug_file = 'dbghelp.dll'
+  full_path = os.path.join(win_sdk_dir, 'Debuggers', target_cpu, debug_file)
+  target_path = os.path.join(target_dir, debug_file)
+  _CopyRuntimeImpl(target_path, full_path)
+
 
 def _GetDesiredVsToolchainHashes():
   """Load a list of SHA1s corresponding to the toolchains that we want installed
   to build with."""
   env_version = GetVisualStudioVersion()
   if env_version == '2015':
     # Update 3 final with patches with 10.0.14393.0 SDK.
     return ['d3cb0e37bdd120ad0ac4650b674b09e81be45616']
   if env_version == '2017':
     # VS 2017 RTM with 10.0.14393.0 SDK and dbghelp.dll fixes.
@@ skipping 94 matching lines @@
       'copy_dlls': CopyDlls,
   }
   if len(sys.argv) < 2 or sys.argv[1] not in commands:
     print >>sys.stderr, 'Expected one of: %s' % ', '.join(commands)
     return 1
   return commands[sys.argv[1]](*sys.argv[2:])
 
 
 if __name__ == '__main__':
   sys.exit(main())