diff --git a/syntax_checkers/cpp.vim b/syntax_checkers/cpp.vim
index 20528e47..16bebde3 100644
--- a/syntax_checkers/cpp.vim
+++ b/syntax_checkers/cpp.vim
@@ -113,7 +113,7 @@ function! SyntaxCheckers_cpp_GetLocList()
     endif
 
     " add optional config file parameters
-    let makeprg .= syntastic#c#ReadConfig(g:syntastic_cpp_config_file)
+    let makeprg .= ' ' . syntastic#c#ReadConfig(g:syntastic_cpp_config_file)
 
     " process makeprg
     let errors = SyntasticMake({ 'makeprg': makeprg,