Fix crash generating debug info for constructor for anonymous struct.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@93601 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index ab8f663..cc97d19 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -1001,7 +1001,7 @@
   const Decl *D = GD.getDecl();
   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
     Name = getFunctionName(FD);
-    if (Name[0] == '\01')
+    if (!Name.empty() && Name[0] == '\01')
       Name = Name.substr(1);
     // Use mangled name as linkage name for c/c++ functions.
     LinkageName = CGM.getMangledName(GD);
diff --git a/test/CodeGenCXX/debug-info.cpp b/test/CodeGenCXX/debug-info.cpp
index 705491e..cb6e830 100644
--- a/test/CodeGenCXX/debug-info.cpp
+++ b/test/CodeGenCXX/debug-info.cpp
@@ -18,3 +18,9 @@
   int B::*a = 0;
   void (B::*b)() = 0;
 }
+
+namespace EmptyNameCrash {
+  struct A { A(); };
+  typedef struct { A x; } B;
+  B x;
+}