diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h
@@ -209,6 +209,9 @@
    private:
     const Symbolizer *sym_;
   };
+
+  // Calls `LateInitialize()` on all `SymbolizerTool` in `tools_`.
+  void LateInitializeTools();
 };
 
 #ifdef SANITIZER_WINDOWS
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.cpp
@@ -126,4 +126,10 @@
     sym_->end_hook_();
 }
 
+void Symbolizer::LateInitializeTools() {
+  for (auto &tool : tools_) {
+    tool.LateInitialize();
+  }
+}
+
 }  // namespace __sanitizer
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_internal.h b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_internal.h
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_internal.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_internal.h
@@ -69,6 +69,11 @@
   virtual const char *Demangle(const char *name) {
     return nullptr;
   }
+
+  // Called during the LateInitialize phase of Sanitizer initialization.
+  // Usually this is a safe to call code that might need to use user memory
+  // allocators.
+  virtual void LateInitialize() {}
 };
 
 // SymbolizerProcess encapsulates communication between the tool and
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_markup.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_markup.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_markup.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_markup.cpp
@@ -94,7 +94,9 @@
   return new (symbolizer_allocator_) Symbolizer({});
 }
 
-void Symbolizer::LateInitialize() { Symbolizer::GetOrInit(); }
+void Symbolizer::LateInitialize() {
+  Symbolizer::GetOrInit()->LateInitializeTools();
+}
 
 void StartReportDeadlySignal() {}
 void ReportDeadlySignal(const SignalContext &sig, u32 tid,
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp
@@ -488,7 +488,7 @@
 }
 
 void Symbolizer::LateInitialize() {
-  Symbolizer::GetOrInit();
+  Symbolizer::GetOrInit()->LateInitializeTools();
   InitializeSwiftDemangler();
 }
 
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
@@ -310,7 +310,7 @@
 }
 
 void Symbolizer::LateInitialize() {
-  Symbolizer::GetOrInit();
+  Symbolizer::GetOrInit()->LateInitializeTools();
 }
 
 }  // namespace __sanitizer