diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cpp
@@ -133,16 +133,13 @@
   }
 }
 
-#ifdef __clang__
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wframe-larger-than="
-#endif
 bool WinSymbolizerTool::SymbolizePC(uptr addr, SymbolizedStack *frame) {
   InitializeDbgHelpIfNeeded();
 
   // See https://docs.microsoft.com/en-us/windows/win32/debug/retrieving-symbol-information-by-address
-  char buffer[sizeof(SYMBOL_INFO) + MAX_SYM_NAME * sizeof(CHAR)];
-  PSYMBOL_INFO symbol = (PSYMBOL_INFO)buffer;
+  InternalMmapVector<char> buffer(sizeof(SYMBOL_INFO) +
+                                  MAX_SYM_NAME * sizeof(CHAR));
+  PSYMBOL_INFO symbol = (PSYMBOL_INFO)&buffer[0];
   symbol->SizeOfStruct = sizeof(SYMBOL_INFO);
   symbol->MaxNameLen = MAX_SYM_NAME;
   DWORD64 offset = 0;
@@ -166,9 +163,6 @@
   // Otherwise, try llvm-symbolizer.
   return got_fileline;
 }
-#ifdef __clang__
-#pragma clang diagnostic pop
-#endif
 
 const char *WinSymbolizerTool::Demangle(const char *name) {
   CHECK(is_dbghelp_initialized);
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_win.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_win.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_win.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_win.cpp
@@ -590,12 +590,13 @@
   // IMAGE_FILE_HEADER
   // IMAGE_OPTIONAL_HEADER
   // Seek to e_lfanew and read all that data.
-  char buf[4 + sizeof(IMAGE_FILE_HEADER) + sizeof(IMAGE_OPTIONAL_HEADER)];
+  InternalMmapVector<char> buf(4 + sizeof(IMAGE_FILE_HEADER) +
+                               sizeof(IMAGE_OPTIONAL_HEADER));
   if (::SetFilePointer(fd, dos_header.e_lfanew, nullptr, FILE_BEGIN) ==
       INVALID_SET_FILE_POINTER)
     return 0;
-  if (!ReadFromFile(fd, &buf[0], sizeof(buf), &bytes_read) ||
-      bytes_read != sizeof(buf))
+  if (!ReadFromFile(fd, &buf[0], buf.size(), &bytes_read) ||
+      bytes_read != buf.size())
     return 0;
 
   // Check for "PE\0\0" before the PE header.
@@ -615,10 +616,6 @@
   return (uptr)pe_header->ImageBase;
 }
 
-#ifdef __clang__
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wframe-larger-than="
-#endif
 void ListOfModules::init() {
   clearOrInit();
   HANDLE cur_process = GetCurrentProcess();
@@ -650,15 +647,15 @@
       continue;
 
     // Get the UTF-16 path and convert to UTF-8.
-    wchar_t modname_utf16[kMaxPathLength];
+    InternalMmapVector<wchar_t> modname_utf16(kMaxPathLength);
     int modname_utf16_len =
-        GetModuleFileNameW(handle, modname_utf16, kMaxPathLength);
+        GetModuleFileNameW(handle, &modname_utf16[0], kMaxPathLength);
     if (modname_utf16_len == 0)
       modname_utf16[0] = '\0';
-    char module_name[kMaxPathLength];
-    int module_name_len =
-        ::WideCharToMultiByte(CP_UTF8, 0, modname_utf16, modname_utf16_len + 1,
-                              &module_name[0], kMaxPathLength, NULL, NULL);
+    InternalMmapVector<char> module_name(kMaxPathLength);
+    int module_name_len = ::WideCharToMultiByte(
+        CP_UTF8, 0, &modname_utf16[0], modname_utf16_len + 1, &module_name[0],
+        kMaxPathLength, NULL, NULL);
     module_name[module_name_len] = '\0';
 
     uptr base_address = (uptr)mi.lpBaseOfDll;
@@ -671,18 +668,15 @@
     uptr preferred_base = GetPreferredBase(&module_name[0]);
     uptr adjusted_base = base_address - preferred_base;
 
-    LoadedModule cur_module;
-    cur_module.set(module_name, adjusted_base);
+    modules_.push_back(LoadedModule());
+    LoadedModule &cur_module = modules_.back();
+    cur_module.set(&module_name[0], adjusted_base);
     // We add the whole module as one single address range.
     cur_module.addAddressRange(base_address, end_address, /*executable*/ true,
                                /*writable*/ true);
-    modules_.push_back(cur_module);
   }
   UnmapOrDie(hmodules, modules_buffer_size);
 }
-#ifdef __clang__
-#pragma clang diagnostic pop
-#endif
 
 void ListOfModules::fallbackInit() { clear(); }
 
@@ -1057,15 +1051,16 @@
     return 0;
 
   // Get the UTF-16 path and convert to UTF-8.
-  wchar_t binname_utf16[kMaxPathLength];
+  InternalMmapVector<wchar_t> binname_utf16(kMaxPathLength);
   int binname_utf16_len =
-      GetModuleFileNameW(NULL, binname_utf16, ARRAY_SIZE(binname_utf16));
+      GetModuleFileNameW(NULL, &binname_utf16[0], kMaxPathLength);
   if (binname_utf16_len == 0) {
     buf[0] = '\0';
     return 0;
   }
-  int binary_name_len = ::WideCharToMultiByte(
-      CP_UTF8, 0, binname_utf16, binname_utf16_len, buf, buf_len, NULL, NULL);
+  int binary_name_len =
+      ::WideCharToMultiByte(CP_UTF8, 0, &binname_utf16[0], binname_utf16_len,
+                            buf, buf_len, NULL, NULL);
   if ((unsigned)binary_name_len == buf_len)
     --binary_name_len;
   buf[binary_name_len] = '\0';