From c00f43a33f7d511b619d676a9931d1b50e07414d Mon Sep 17 00:00:00 2001
From: Argyrios Kyrtzidis <akyrtzi@gmail.com>
Date: Mon, 18 Mar 2013 22:55:24 +0000
Subject: [PATCH] [frontend] Initialize the diagnostic client before loading an
 ast file.

Issue reported by Tom Honermann!
http://llvm.org/bugs/show_bug.cgi?id=15377

llvm-svn: 177336
---
 clang/lib/Frontend/FrontendAction.cpp |  4 ++++
 clang/test/Frontend/ast-main.cpp      | 22 ++++++++++++++++++++++
 2 files changed, 26 insertions(+)
 create mode 100644 clang/test/Frontend/ast-main.cpp

diff --git a/clang/lib/Frontend/FrontendAction.cpp b/clang/lib/Frontend/FrontendAction.cpp
index 6d31c31..c47423c 100644
--- a/clang/lib/Frontend/FrontendAction.cpp
+++ b/clang/lib/Frontend/FrontendAction.cpp
@@ -188,6 +188,10 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
 
     setCurrentInput(Input, AST);
 
+    // Inform the diagnostic client we are processing a source file.
+    CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(), 0);
+    HasBegunSourceFile = true;
+
     // Set the shared objects, these are reset when we finish processing the
     // file, otherwise the CompilerInstance will happily destroy them.
     CI.setFileManager(&AST->getFileManager());
diff --git a/clang/test/Frontend/ast-main.cpp b/clang/test/Frontend/ast-main.cpp
new file mode 100644
index 0000000..d3d8471
--- /dev/null
+++ b/clang/test/Frontend/ast-main.cpp
@@ -0,0 +1,22 @@
+// RUN: %clang -emit-llvm -S -o %t1.ll -x c++ - < %s
+// RUN: %clang -emit-ast -o %t.ast %s
+// RUN: %clang -emit-llvm -S -o %t2.ll -x ast - < %t.ast
+// RUN: diff %t1.ll %t2.ll
+
+// http://llvm.org/bugs/show_bug.cgi?id=15377
+template<typename T>
+struct S {
+    T *mf();
+};
+template<typename T>
+T *S<T>::mf() {
+    // warning: control reaches end of non-void function [-Wreturn-type]
+}
+
+void f() {
+    S<int>().mf();
+}
+
+int main() {
+  return 0;
+}
-- 
2.7.4