diff --git a/compiler/ast.nim b/compiler/ast.nim
index db6003b874..4f0b47b851 100644
--- a/compiler/ast.nim
+++ b/compiler/ast.nim
@@ -610,7 +610,7 @@ const
   # thus cannot be overloaded (also documented in the spec!):
   SpecialSemMagics* = {
     mDefined, mDefinedInScope, mCompiles, mLow, mHigh, mSizeOf, mIs, mOf, 
-    mEcho, mShallowCopy, mExpandToAst, mParallel, mSpawn}
+    mEcho, mShallowCopy, mExpandToAst, mParallel, mSpawn, mAstToStr}
 
 type
   PNode* = ref TNode