diff --git a/mlir/lib/IR/Block.cpp b/mlir/lib/IR/Block.cpp
--- a/mlir/lib/IR/Block.cpp
+++ b/mlir/lib/IR/Block.cpp
@@ -346,8 +346,8 @@
 SuccessorRange::SuccessorRange() : SuccessorRange(nullptr, 0) {}
 
 SuccessorRange::SuccessorRange(Block *block) : SuccessorRange() {
-  if (!llvm::hasSingleElement(*block->getParent())) {
-    Operation *term = block->getTerminator();
+  if (!block->empty() && !llvm::hasSingleElement(*block->getParent())) {
+    Operation *term = &block->back();
     if ((count = term->getNumSuccessors()))
       base = term->getBlockOperands().data();
   }
diff --git a/mlir/test/IR/invalid.mlir b/mlir/test/IR/invalid.mlir
--- a/mlir/test/IR/invalid.mlir
+++ b/mlir/test/IR/invalid.mlir
@@ -176,6 +176,16 @@
   %y = constant 1 : i32  // expected-error {{block with no terminator}}
 }
 
+// -----
+
+func @no_terminator() {
+  br ^bb1
+^bb1:
+  %x = constant 0 : i32
+  %y = constant 1 : i32  // expected-error {{block with no terminator}}
+}
+
+
 // -----
 
 "       // expected-error {{expected}}