described workaround for ThreadSanitizer error in README.md

README.md

@@ -370,6 +370,10 @@ Important Notes
   performance measurements, explicit initialization is strongly recommended
   performance measurements, explicit initialization is strongly recommended
   since the measurements will otherwise include the initialization time of
   since the measurements will otherwise include the initialization time of
   MTAPI.
   MTAPI.
+- When using ThreadSanitizer there is a bug that causes the built-in CMake type
+  size determination to fail which in turn leads to a broken configuration.
+  Therefore, you have to do a normal build first and then rerun CMake with
+  flags and libs configured for ThreadSanitizer.
 
 
 
 
 Links
 Links