src/os/windows/vm/os_windows.cpp

*** 5002,5012 ****
    if (++mallocDebugIntervalCounter >= MallocVerifyInterval || force) {
      // Note: HeapValidate executes two hardware breakpoints when it finds something
      // wrong; at these points, eax contains the address of the offending block (I think).
      // To get to the exlicit error message(s) below, just continue twice.
      HANDLE heap = GetProcessHeap();
!     { HeapLock(heap);
        PROCESS_HEAP_ENTRY phe;
        phe.lpData = NULL;
        while (HeapWalk(heap, &phe) != 0) {
          if ((phe.wFlags & PROCESS_HEAP_ENTRY_BUSY) &&
              !HeapValidate(heap, 0, phe.lpData)) {
--- 5002,5016 ----
    if (++mallocDebugIntervalCounter >= MallocVerifyInterval || force) {
      // Note: HeapValidate executes two hardware breakpoints when it finds something
      // wrong; at these points, eax contains the address of the offending block (I think).
      // To get to the exlicit error message(s) below, just continue twice.
      HANDLE heap = GetProcessHeap();
! 
!     // If we fail to lock the heap, then gflags.exe has been used
!     // or some other special heap flag has been set that prevents
!     // locking. We don't try to walk a heap we can't lock.
!     if (HeapLock(heap) != 0) { 
        PROCESS_HEAP_ENTRY phe;
        phe.lpData = NULL;
        while (HeapWalk(heap, &phe) != 0) {
          if ((phe.wFlags & PROCESS_HEAP_ENTRY_BUSY) &&
              !HeapValidate(heap, 0, phe.lpData)) {