diff --git a/Source/cmAddCustomTargetCommand.cxx b/Source/cmAddCustomTargetCommand.cxx
index 085a80d48..d7e479a66 100644
--- a/Source/cmAddCustomTargetCommand.cxx
+++ b/Source/cmAddCustomTargetCommand.cxx
@@ -159,12 +159,14 @@ bool cmAddCustomTargetCommand
     }
 
   // Enforce name uniqueness.
+  {
   std::string msg;
   if(!this->Makefile->EnforceUniqueName(args[0], msg))
     {
     this->SetError(msg.c_str());
     return false;
     }
+  }
 
   // Add the utility target to the makefile.
   bool escapeOldStyle = !verbatim;
diff --git a/Source/cmAddExecutableCommand.cxx b/Source/cmAddExecutableCommand.cxx
index 744506969..bd3623ff1 100644
--- a/Source/cmAddExecutableCommand.cxx
+++ b/Source/cmAddExecutableCommand.cxx
@@ -101,12 +101,14 @@ bool cmAddExecutableCommand
     }
 
   // Enforce name uniqueness.
+  {
   std::string msg;
   if(!this->Makefile->EnforceUniqueName(exename, msg))
     {
     this->SetError(msg.c_str());
     return false;
     }
+  }
 
   if (s == args.end())
     {
diff --git a/Source/cmAddLibraryCommand.cxx b/Source/cmAddLibraryCommand.cxx
index 389672243..575dd04f2 100644
--- a/Source/cmAddLibraryCommand.cxx
+++ b/Source/cmAddLibraryCommand.cxx
@@ -128,12 +128,14 @@ bool cmAddLibraryCommand
     }
 
   // Enforce name uniqueness.
+  {
   std::string msg;
   if(!this->Makefile->EnforceUniqueName(libName, msg))
     {
     this->SetError(msg.c_str());
     return false;
     }
+  }
 
   if (s == args.end())
     {