Index: lib/asan/asan_errors.h
===================================================================
--- lib/asan/asan_errors.h
+++ lib/asan/asan_errors.h
@@ -141,12 +141,35 @@
   void Print();
 };
 
+struct ErrorAllocTypeMismatch : ErrorBase {
+  u32 tid;
+  HeapAddressDescription addr_description;
+  // ErrorAllocTypeMismatch doesn't own the stack trace.
+  BufferedStackTrace *dealloc_stack;
+  AllocType alloc_type, dealloc_type;
+  // VS2013 doesn't implement unrestricted unions, so we need a trivial default
+  // constructor
+  ErrorAllocTypeMismatch() = default;
+  ErrorAllocTypeMismatch(uptr addr, u32 tid_, BufferedStackTrace *stack,
+                         AllocType alloc_type_, AllocType dealloc_type_)
+      : tid(tid_),
+        dealloc_stack(stack),
+        alloc_type(alloc_type_),
+        dealloc_type(dealloc_type_) {
+    GetHeapAddressInformation(addr, 1, &addr_description);
+    scariness.Clear();
+    scariness.Scare(10, "alloc-dealloc-mismatch");
+  };
+  void Print();
+};
+
 #define FOR_EACH_ERROR_KIND_MEMBER_NAME_PAIR(macro)      \
   macro(StackOverflow, stack_overflow)                   \
   macro(DeadlySignal, deadly_signal)                     \
   macro(DoubleFree, double_free)                         \
   macro(NewDeleteSizeMismatch, new_delete_size_mismatch) \
-  macro(FreeNotMalloced, free_not_malloced)
+  macro(FreeNotMalloced, free_not_malloced)              \
+  macro(AllocTypeMismatch, alloc_type_mismatch)
 
 enum ErrorKind {
   kErrorKindInvalid = 0,
Index: lib/asan/asan_errors.cc
===================================================================
--- lib/asan/asan_errors.cc
+++ lib/asan/asan_errors.cc
@@ -141,4 +141,27 @@
   ReportErrorSummary("bad-free", &stack);
 }
 
+void ErrorAllocTypeMismatch::Print() {
+  static const char *alloc_names[] = {"INVALID", "malloc", "operator new",
+                                      "operator new []"};
+  static const char *dealloc_names[] = {"INVALID", "free", "operator delete",
+                                        "operator delete []"};
+  CHECK_NE(alloc_type, dealloc_type);
+  Decorator d;
+  Printf("%s", d.Warning());
+  Report("ERROR: AddressSanitizer: alloc-dealloc-mismatch (%s vs %s) on %p\n",
+         alloc_names[alloc_type], dealloc_names[dealloc_type],
+         addr_description.addr);
+  Printf("%s", d.EndWarning());
+  CHECK_GT(dealloc_stack->size, 0);
+  scariness.Print();
+  GET_STACK_TRACE_FATAL(dealloc_stack->trace[0], dealloc_stack->top_frame_bp);
+  stack.Print();
+  addr_description.Print();
+  ReportErrorSummary("alloc-dealloc-mismatch", &stack);
+  Report(
+      "HINT: if you don't care about these errors you may set "
+      "ASAN_OPTIONS=alloc_dealloc_mismatch=0\n");
+}
+
 }  // namespace __asan
Index: lib/asan/asan_report.cc
===================================================================
--- lib/asan/asan_report.cc
+++ lib/asan/asan_report.cc
@@ -357,25 +357,10 @@
 void ReportAllocTypeMismatch(uptr addr, BufferedStackTrace *free_stack,
                              AllocType alloc_type,
                              AllocType dealloc_type) {
-  static const char *alloc_names[] =
-    {"INVALID", "malloc", "operator new", "operator new []"};
-  static const char *dealloc_names[] =
-    {"INVALID", "free", "operator delete", "operator delete []"};
-  CHECK_NE(alloc_type, dealloc_type);
   ScopedInErrorReport in_report;
-  Decorator d;
-  Printf("%s", d.Warning());
-  Report("ERROR: AddressSanitizer: alloc-dealloc-mismatch (%s vs %s) on %p\n",
-        alloc_names[alloc_type], dealloc_names[dealloc_type], addr);
-  Printf("%s", d.EndWarning());
-  CHECK_GT(free_stack->size, 0);
-  ScarinessScore::PrintSimple(10, "alloc-dealloc-mismatch");
-  GET_STACK_TRACE_FATAL(free_stack->trace[0], free_stack->top_frame_bp);
-  stack.Print();
-  DescribeAddressIfHeap(addr);
-  ReportErrorSummary("alloc-dealloc-mismatch", &stack);
-  Report("HINT: if you don't care about these errors you may set "
-         "ASAN_OPTIONS=alloc_dealloc_mismatch=0\n");
+  ErrorAllocTypeMismatch error(addr, GetCurrentTidOrInvalid(), free_stack,
+                               alloc_type, dealloc_type);
+  in_report.ReportError(error);
 }
 
 void ReportMallocUsableSizeNotOwned(uptr addr, BufferedStackTrace *stack) {