The mysterious bug turns out to be an incredibly bone-headed mistake.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70160 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseStmt.cpp b/lib/Parse/ParseStmt.cpp
index ce88728..35348d5 100644
--- a/lib/Parse/ParseStmt.cpp
+++ b/lib/Parse/ParseStmt.cpp
@@ -1324,11 +1324,12 @@
   if (Tok.is(tok::colon))
     ParseConstructorInitializer(Decl);
 
+  SourceLocation LBraceLoc = Tok.getLocation();
   OwningStmtResult FnBody(ParseCXXTryBlockCommon(TryLoc));
   // If we failed to parse the try-catch, we just give the function an empty
   // compound statement as the body.
   if (FnBody.isInvalid())
-    FnBody = Actions.ActOnCompoundStmt(TryLoc, TryLoc,
+    FnBody = Actions.ActOnCompoundStmt(LBraceLoc, LBraceLoc,
                                        MultiStmtArg(Actions), false);
 
   return Actions.ActOnFinishFunctionBody(Decl, move(FnBody));