Index: compiler-rt/trunk/lib/sanitizer_common/sanitizer_dbghelp.h
===================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_dbghelp.h
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_dbghelp.h
@@ -0,0 +1,42 @@
+//===-- sanitizer_dbghelp.h ------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Wrappers for lazy loaded dbghelp.dll. Provides function pointers and a
+// callback to initialize them.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SANITIZER_SYMBOLIZER_WIN_H
+#define SANITIZER_SYMBOLIZER_WIN_H
+
+#if !SANITIZER_WINDOWS
+#error "sanitizer_dbghelp.h is a Windows-only header"
+#endif
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <dbghelp.h>
+
+namespace __sanitizer {
+
+extern decltype(::StackWalk64) *StackWalk64;
+extern decltype(::SymCleanup) *SymCleanup;
+extern decltype(::SymFromAddr) *SymFromAddr;
+extern decltype(::SymFunctionTableAccess64) *SymFunctionTableAccess64;
+extern decltype(::SymGetLineFromAddr64) *SymGetLineFromAddr64;
+extern decltype(::SymGetModuleBase64) *SymGetModuleBase64;
+extern decltype(::SymGetSearchPathW) *SymGetSearchPathW;
+extern decltype(::SymInitialize) *SymInitialize;
+extern decltype(::SymSetOptions) *SymSetOptions;
+extern decltype(::SymSetSearchPathW) *SymSetSearchPathW;
+extern decltype(::UnDecorateSymbolName) *UnDecorateSymbolName;
+
+}  // namespace __sanitizer
+
+#endif  // SANITIZER_SYMBOLIZER_WIN_H
Index: compiler-rt/trunk/lib/sanitizer_common/sanitizer_symbolizer_win.cc
===================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_symbolizer_win.cc
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_symbolizer_win.cc
@@ -14,15 +14,24 @@
 
 #include "sanitizer_platform.h"
 #if SANITIZER_WINDOWS
-#define WIN32_LEAN_AND_MEAN
-#include <windows.h>
-#include <dbghelp.h>
-#pragma comment(lib, "dbghelp.lib")
 
+#include "sanitizer_dbghelp.h"
 #include "sanitizer_symbolizer_internal.h"
 
 namespace __sanitizer {
 
+decltype(::StackWalk64) *StackWalk64;
+decltype(::SymCleanup) *SymCleanup;
+decltype(::SymFromAddr) *SymFromAddr;
+decltype(::SymFunctionTableAccess64) *SymFunctionTableAccess64;
+decltype(::SymGetLineFromAddr64) *SymGetLineFromAddr64;
+decltype(::SymGetModuleBase64) *SymGetModuleBase64;
+decltype(::SymGetSearchPathW) *SymGetSearchPathW;
+decltype(::SymInitialize) *SymInitialize;
+decltype(::SymSetOptions) *SymSetOptions;
+decltype(::SymSetSearchPathW) *SymSetSearchPathW;
+decltype(::UnDecorateSymbolName) *UnDecorateSymbolName;
+
 namespace {
 
 class WinSymbolizerTool : public SymbolizerTool {
@@ -50,6 +59,29 @@
 void InitializeDbgHelpIfNeeded() {
   if (is_dbghelp_initialized)
     return;
+
+  HMODULE dbghelp = LoadLibraryA("dbghelp.dll");
+  CHECK(dbghelp && "failed to load dbghelp.dll");
+
+#define DBGHELP_IMPORT(name)                                                  \
+  do {                                                                        \
+    name =                                                                    \
+        reinterpret_cast<decltype(::name) *>(GetProcAddress(dbghelp, #name)); \
+    CHECK(name != nullptr);                                                   \
+  } while (0)
+  DBGHELP_IMPORT(StackWalk64);
+  DBGHELP_IMPORT(SymCleanup);
+  DBGHELP_IMPORT(SymFromAddr);
+  DBGHELP_IMPORT(SymFunctionTableAccess64);
+  DBGHELP_IMPORT(SymGetLineFromAddr64);
+  DBGHELP_IMPORT(SymGetModuleBase64);
+  DBGHELP_IMPORT(SymGetSearchPathW);
+  DBGHELP_IMPORT(SymInitialize);
+  DBGHELP_IMPORT(SymSetOptions);
+  DBGHELP_IMPORT(SymSetSearchPathW);
+  DBGHELP_IMPORT(UnDecorateSymbolName);
+#undef DBGHELP_IMPORT
+
   if (!TrySymInitialize()) {
     // OK, maybe the client app has called SymInitialize already.
     // That's a bit unfortunate for us as all the DbgHelp functions are
Index: compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc
===================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_win.cc
@@ -18,12 +18,12 @@
 #define WIN32_LEAN_AND_MEAN
 #define NOGDI
 #include <windows.h>
-#include <dbghelp.h>
 #include <io.h>
 #include <psapi.h>
 #include <stdlib.h>
 
 #include "sanitizer_common.h"
+#include "sanitizer_dbghelp.h"
 #include "sanitizer_libc.h"
 #include "sanitizer_mutex.h"
 #include "sanitizer_placement_new.h"
@@ -781,8 +781,8 @@
   stack_frame.AddrFrame.Mode = AddrModeFlat;
   stack_frame.AddrStack.Mode = AddrModeFlat;
   while (StackWalk64(machine_type, GetCurrentProcess(), GetCurrentThread(),
-                     &stack_frame, &ctx, NULL, &SymFunctionTableAccess64,
-                     &SymGetModuleBase64, NULL) &&
+                     &stack_frame, &ctx, NULL, SymFunctionTableAccess64,
+                     SymGetModuleBase64, NULL) &&
          size < Min(max_depth, kStackTraceMax)) {
     trace_buffer[size++] = (uptr)stack_frame.AddrPC.Offset;
   }
Index: compiler-rt/trunk/test/CMakeLists.txt
===================================================================
--- compiler-rt/trunk/test/CMakeLists.txt
+++ compiler-rt/trunk/test/CMakeLists.txt
@@ -23,7 +23,7 @@
     # Use LLVM utils and Clang from the same build tree.
     list(APPEND SANITIZER_COMMON_LIT_TEST_DEPS
       clang clang-headers FileCheck count not llvm-config llvm-nm llvm-objdump
-      llvm-symbolizer compiler-rt-headers sancov)
+      llvm-readobj llvm-symbolizer compiler-rt-headers sancov)
     if (COMPILER_RT_HAS_PROFILE)
       list(APPEND SANITIZER_COMMON_LIT_TEST_DEPS profile)
     endif()
Index: compiler-rt/trunk/test/asan/TestCases/Windows/delay_dbghelp.cc
===================================================================
--- compiler-rt/trunk/test/asan/TestCases/Windows/delay_dbghelp.cc
+++ compiler-rt/trunk/test/asan/TestCases/Windows/delay_dbghelp.cc
@@ -0,0 +1,18 @@
+// Build an executable with ASan, then extract the DLLs that it depends on.
+// RUN: %clang_cl_asan %s -Fe%t.exe
+// RUN: llvm-readobj -coff-imports %t.exe | grep Name: | sed -e 's/ *Name: *//' > %t
+//
+// Make sure the binary doesn't depend on dbghelp directly.
+// RUN: not grep dbghelp.dll %t
+//
+// Make sure any clang_rt DLLs it depends on don't depend on dbghelp. In the
+// static build, there won't be any clang_rt DLLs.
+// RUN: not grep cl""ang_rt %t || \
+// RUN:   grep cl""ang_rt %t | xargs which | \
+// RUN:   xargs llvm-readobj -coff-imports | not grep dbghelp.dll %t
+
+extern "C" int puts(const char *);
+
+int main() {
+  puts("main");
+}