Can't have arrays of auto.

llvm-svn: 74314

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -401,6 +401,8 @@ def note_uninit_reference_member : Note<
 // C++0x auto
 def err_auto_variable_cannot_appear_in_own_initializer : Error<
   "variable %0 declared with 'auto' type cannot appear in its own initializer">;
+def err_illegal_decl_array_of_auto : Error<
+  "'%0' declared as array of 'auto'">;
   
 // Objective-C++
 def err_objc_decls_may_only_appear_in_global_scope : Error<

clang/lib/Sema/SemaType.cpp

@@ -498,6 +498,12 @@ QualType Sema::BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM,
     return QualType();
   } 
 
+  if (Context.getCanonicalType(T) == Context.UndeducedAutoTy) {
+    Diag(Loc,  diag::err_illegal_decl_array_of_auto) 
+      << getPrintableNameForEntity(Entity);
+    return QualType();
+  }
+  
   if (const RecordType *EltTy = T->getAsRecordType()) {
     // If the element type is a struct or union that contains a variadic
     // array, accept it as a GNU extension: C99 6.7.2.1p2.

clang/test/CXX/dcl.decl/dcl.meaning/dcl.array/p1-cxx0x.cpp

@@ -0,0 +1,6 @@
+// RUN: clang-cc -fsyntax-only -verify -std=c++0x
+
+void f() {
+  int b[5];
+  auto a[5] = b; // expected-error{{'a' declared as array of 'auto'}}
+}