Fix PR9488: 'auto' type substitution can fail (for instance, if it creates a reference-to-void type). Don't crash if it does.
Also fix an issue where type source information for the resulting type was being lost.

llvm-svn: 127811
diff --git a/clang/test/SemaCXX/auto-subst-failure.cpp b/clang/test/SemaCXX/auto-subst-failure.cpp
new file mode 100644
index 0000000..442c7e8
--- /dev/null
+++ b/clang/test/SemaCXX/auto-subst-failure.cpp
@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s -std=c++0x
+
+void f() {
+  auto a = f(); // expected-error {{variable has incomplete type 'void'}}
+  auto &b = f(); // expected-error {{cannot form a reference to 'void'}}
+  auto *c = f(); // expected-error {{incompatible initializer of type 'void'}}
+
+  auto d(f()); // expected-error {{variable has incomplete type 'void'}}
+  auto &&e(f()); // expected-error {{cannot form a reference to 'void'}}
+  auto *g(f()); // expected-error {{incompatible initializer of type 'void'}}
+
+  (void)new auto(f()); // expected-error {{allocation of incomplete type 'void'}}
+  (void)new auto&(f()); // expected-error {{cannot form a reference to 'void'}}
+  (void)new auto*(f()); // expected-error {{incompatible constructor argument of type 'void'}}
+}