Index: lib/CodeGen/CodeGenFunction.cpp
===================================================================
--- lib/CodeGen/CodeGenFunction.cpp
+++ lib/CodeGen/CodeGenFunction.cpp
@@ -1298,6 +1298,14 @@
 
   Stmt *Body = FD->getBody();
 
+  // TODO: As mentioned in the TODO added in https://reviews.llvm.org/rL280678,
+  // coro-split is not capable of moving spills whose users' users are not
+  // dominated by 'llvm.coro.begin'. '-fsanitize=null', for example, generates
+  // such code: null checks that occur before 'llvm.coro.begin'. For now,
+  // disable UBSan checks within coroutine function bodies.
+  if (Body && Body->getStmtClass() == Stmt::CoroutineBodyStmtClass)
+    SanOpts.clear();
+
   // Initialize helper which will detect jumps which can cause invalid lifetime
   // markers.
   if (Body && ShouldEmitLifetimeMarkers)