Fix a couple of bugs, add some new cool stuff.

1. Fix a todo in Parser::ParseTag, to recover better.  On code like
   that in test/Sema/decl-invalid.c it causes us to return a single
   error instead of multiple.
2. Fix an error in Sema::ParseDeclarator, where it would crash if the
   declarator didn't have an identifier.  Instead, diagnose the problem.
3. Start adding infrastructure to track the range of locations covered
   by a declspec or declarator.  This is mostly implemented for declspec,
   but could be improved, it is missing for declarator.

Thanks to Neil for pointing out this crash.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@40482 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Parser/function-decls.c b/test/Parser/function-decls.c
new file mode 100644
index 0000000..ef93756
--- /dev/null
+++ b/test/Parser/function-decls.c
@@ -0,0 +1,10 @@
+/* RUN: clang %s -parse-ast-print
+ */
+
+void foo() {
+  int X;
+  X = sizeof(void (*(*)())());
+  X = sizeof(int(*)(int, float, ...));
+  X = sizeof(void (*(int arga, void (*argb)(double Y)))(void* Z));
+}
+