diff --git a/compilerAst/src/prog8/ast/AstToplevel.kt b/compilerAst/src/prog8/ast/AstToplevel.kt
index 06a62579c..015638f3b 100644
--- a/compilerAst/src/prog8/ast/AstToplevel.kt
+++ b/compilerAst/src/prog8/ast/AstToplevel.kt
@@ -427,6 +427,7 @@ fun defaultZero(dt: BaseDataType, position: Position) = when(dt) {
     BaseDataType.BYTE -> NumericLiteral(BaseDataType.BYTE, 0.0,  position)
     BaseDataType.UWORD, BaseDataType.STR -> NumericLiteral(BaseDataType.UWORD, 0.0, position)
     BaseDataType.WORD -> NumericLiteral(BaseDataType.WORD, 0.0, position)
+    BaseDataType.LONG -> NumericLiteral(BaseDataType.LONG, 0.0, position)
     BaseDataType.FLOAT -> NumericLiteral(BaseDataType.FLOAT, 0.0, position)
     BaseDataType.POINTER -> NumericLiteral(BaseDataType.UWORD, 0.0, position)
     else -> throw FatalAstException("can only determine default zero value for a numeric type")