fix 7320: we can't delete a trailing space if it doesn't exist.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@113125 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 1 deletions

diff --git a/lib/Lex/Pragma.cpp b/lib/Lex/Pragma.cpp
index 7975da58b6..a7b289e137 100644
--- a/lib/Lex/Pragma.cpp
+++ b/lib/Lex/Pragma.cpp
@@ -384,7 +384,9 @@ void Preprocessor::HandlePragmaDependency(Token &DependencyTok) {
       Lex(DependencyTok);
     }
 
-    Message.erase(Message.end()-1);
+    // Remove the trailing ' ' if present.
+    if (!Message.empty())
+      Message.erase(Message.end()-1);
     Diag(FilenameTok, diag::pp_out_of_date_dependency) << Message;
   }
 }