diff --git a/clang/lib/Sema/SemaStmt.cpp b/clang/lib/Sema/SemaStmt.cpp
--- a/clang/lib/Sema/SemaStmt.cpp
+++ b/clang/lib/Sema/SemaStmt.cpp
@@ -730,11 +730,11 @@
 
   if (CondExpr && !CondExpr->isTypeDependent()) {
     // We have already converted the expression to an integral or enumeration
-    // type, when we parsed the switch condition. If we don't have an
-    // appropriate type now, enter the switch scope but remember that it's
-    // invalid.
-    assert(CondExpr->getType()->isIntegralOrEnumerationType() &&
-           "invalid condition type");
+    // type, when we parsed the switch condition. There are cases where we don't
+    // have an appropriate type, e.g. a typo-expr Cond was corrected to an
+    // inappropriate-type expr, we just returns an error.
+    if (!CondExpr->getType()->isIntegralOrEnumerationType())
+      return StmtError();
     if (CondExpr->isKnownToHaveBooleanValue()) {
       // switch(bool_expr) {...} is often a programmer error, e.g.
       //   switch(n && mask) { ... }  // Doh - should be "n & mask".
diff --git a/clang/test/Parser/switch-typo-correction.cpp b/clang/test/Parser/switch-typo-correction.cpp
new file mode 100644
--- /dev/null
+++ b/clang/test/Parser/switch-typo-correction.cpp
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+namespace c { double xxx; } // expected-note{{'c::xxx' declared here}}
+namespace d { float xxx; }
+namespace z { namespace xxx {} }
+
+void crash() {
+  switch (xxx) {} // expected-error{{use of undeclared identifier 'xxx'; did you mean }}
+}