diff --git a/src/preprocessor.cpp b/src/preprocessor.cpp
index a52a56627..55639a32f 100644
--- a/src/preprocessor.cpp
+++ b/src/preprocessor.cpp
@@ -751,7 +751,7 @@ std::string Preprocessor::expandMacros(std::string code)
 
             code.erase(pos1, pos2 - pos1);
             code.insert(pos1, macrocode);
-            pos1 += macrocode.length();
+            pos1 += macrocode.length() - 1;
         }
     }