Index: include/sanitizer/common_interface_defs.h
===================================================================
--- include/sanitizer/common_interface_defs.h
+++ include/sanitizer/common_interface_defs.h
@@ -55,6 +55,11 @@
   // the error message. This function can be overridden by the client.
   void __sanitizer_report_error_summary(const char *error_summary);
 
+  // This function is called by the user to provide a callback
+  // for all messages produced by the sanitizer.  The callback
+  // receives the error message.  This function should not be overriden.
+  void __sanitizer_report_message_callback(void (*callback)(const char*));
+
   // Some of the sanitizers (e.g. asan/tsan) may miss bugs that happen
   // in unaligned loads/stores. In order to find such bugs reliably one needs
   // to replace plain unaligned loads/stores with these calls.
Index: lib/asan/asan_interface.inc
===================================================================
--- lib/asan/asan_interface.inc
+++ lib/asan/asan_interface.inc
@@ -164,6 +164,7 @@
 INTERFACE_FUNCTION(__sanitizer_unaligned_store16)
 INTERFACE_FUNCTION(__sanitizer_unaligned_store32)
 INTERFACE_FUNCTION(__sanitizer_unaligned_store64)
+INTERFACE_FUNCTION(__sanitizer_report_message_callback)
 INTERFACE_WEAK_FUNCTION(__asan_default_options)
 INTERFACE_WEAK_FUNCTION(__asan_default_suppressions)
 INTERFACE_WEAK_FUNCTION(__asan_on_error)
Index: lib/asan/asan_rtl.cc
===================================================================
--- lib/asan/asan_rtl.cc
+++ lib/asan/asan_rtl.cc
@@ -396,7 +396,7 @@
   // Install tool-specific callbacks in sanitizer_common.
   AddDieCallback(AsanDie);
   SetCheckFailedCallback(AsanCheckFailed);
-  SetPrintfAndReportCallback(AppendToErrorMessageBuffer);
+  AddPrintfAndReportCallback(AppendToErrorMessageBuffer);
 
   __sanitizer_set_report_path(common_flags()->log_path);
 
Index: lib/sanitizer_common/sanitizer_common.h
===================================================================
--- lib/sanitizer_common/sanitizer_common.h
+++ lib/sanitizer_common/sanitizer_common.h
@@ -221,7 +221,7 @@
 void RemoveANSIEscapeSequencesFromString(char *buffer);
 void Printf(const char *format, ...);
 void Report(const char *format, ...);
-void SetPrintfAndReportCallback(void (*callback)(const char *));
+void AddPrintfAndReportCallback(void (*callback)(const char *));
 #define VReport(level, ...)                                              \
   do {                                                                   \
     if ((uptr)Verbosity() >= (level)) Report(__VA_ARGS__); \
Index: lib/sanitizer_common/sanitizer_common.cc
===================================================================
--- lib/sanitizer_common/sanitizer_common.cc
+++ lib/sanitizer_common/sanitizer_common.cc
@@ -358,6 +358,11 @@
 }
 
 SANITIZER_INTERFACE_ATTRIBUTE
+void __sanitizer_report_message_callback(void (*callback)(const char*)){
+  AddPrintfAndReportCallback(callback);
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE
 void __sanitizer_set_death_callback(void (*callback)(void)) {
   SetUserDieCallback(callback);
 }
Index: lib/sanitizer_common/sanitizer_common_interface.inc
===================================================================
--- lib/sanitizer_common/sanitizer_common_interface.inc
+++ lib/sanitizer_common/sanitizer_common_interface.inc
@@ -15,6 +15,7 @@
 INTERFACE_FUNCTION(__sanitizer_set_report_fd)
 INTERFACE_FUNCTION(__sanitizer_verify_contiguous_container)
 INTERFACE_WEAK_FUNCTION(__sanitizer_report_error_summary)
+INTERFACE_WEAK_FUNCTION(__sanitizer_report_message_callback)
 INTERFACE_WEAK_FUNCTION(__sanitizer_sandbox_on_notify)
 // Sanitizer weak hooks
 INTERFACE_WEAK_FUNCTION(__sanitizer_weak_hook_memcmp)
Index: lib/sanitizer_common/sanitizer_printf.cc
===================================================================
--- lib/sanitizer_common/sanitizer_printf.cc
+++ lib/sanitizer_common/sanitizer_printf.cc
@@ -206,9 +206,17 @@
   return result;
 }
 
-static void (*PrintfAndReportCallback)(const char *);
-void SetPrintfAndReportCallback(void (*callback)(const char *)) {
-  PrintfAndReportCallback = callback;
+#define MAX_PRINTF_AND_REPORT_CALLBACKS 8
+static void (*PrintfAndReportCallbacks[MAX_PRINTF_AND_REPORT_CALLBACKS])(const char *);
+static int PrintfAndReportCallbacksSize = 0;
+
+void AddPrintfAndReportCallback(void (*callback)(const char *)) {
+  CHECK(callback);
+  CHECK_LT(PrintfAndReportCallbacksSize, MAX_PRINTF_AND_REPORT_CALLBACKS);
+  CHECK(!PrintfAndReportCallbacks[PrintfAndReportCallbacksSize]);
+
+  PrintfAndReportCallbacks[PrintfAndReportCallbacksSize] = callback;
+  PrintfAndReportCallbacksSize++;
 }
 
 // Can be overriden in frontend.
@@ -223,8 +231,8 @@
 
 static void CallPrintfAndReportCallback(const char *str) {
   OnPrint(str);
-  if (PrintfAndReportCallback)
-    PrintfAndReportCallback(str);
+  for (int i = 0; i < PrintfAndReportCallbacksSize; ++i)
+    PrintfAndReportCallbacks[i](str);
 }
 
 static void NOINLINE SharedPrintfCodeNoBuffer(bool append_pid,
Index: test/asan/TestCases/error_report_callback.cc
===================================================================
--- test/asan/TestCases/error_report_callback.cc
+++ test/asan/TestCases/error_report_callback.cc
@@ -11,6 +11,7 @@
 
 int main(int argc, char **argv) {
   __asan_set_error_report_callback(ErrorReportCallbackOneToZ);
+  __sanitizer_report_message_callback(ErrorReportCallbackOneToZ);
   __asan_report_error(
       (void *)__builtin_extract_return_addr(__builtin_return_address(0)), 0, 0,
       0, true, 1);