diff --git a/src/main/scala/millfork/parser/MfParser.scala b/src/main/scala/millfork/parser/MfParser.scala
index f6aea14e..ae4df02e 100644
--- a/src/main/scala/millfork/parser/MfParser.scala
+++ b/src/main/scala/millfork/parser/MfParser.scala
@@ -562,17 +562,17 @@ abstract class MfParser[T](fileId: String, input: String, currentDirectory: Stri
   } yield {
     if (flags("interrupt") && flags("macro")) log.error(s"Interrupt function `$name` cannot be macros", Some(p))
     if (flags("kernal_interrupt") && flags("macro")) log.error(s"Kernal interrupt function `$name` cannot be macros", Some(p))
-    if (flags("interrupt") && flags("reentrant")) log.error("Interrupt function `$name` cannot be reentrant", Some(p))
-    if (flags("interrupt") && flags("kernal_interrupt")) log.error("Interrupt function `$name` cannot be a Kernal interrupt", Some(p))
+    if (flags("interrupt") && flags("reentrant")) log.error(s"Interrupt function `$name` cannot be reentrant", Some(p))
+    if (flags("interrupt") && flags("kernal_interrupt")) log.error(s"Interrupt function `$name` cannot be a Kernal interrupt", Some(p))
     if (flags("macro") && flags("reentrant")) log.error("Reentrant and macro exclude each other", Some(p))
     if (flags("inline") && flags("noinline")) log.error("Noinline and inline exclude each other", Some(p))
     if (flags("macro") && flags("noinline")) log.error("Noinline and macro exclude each other", Some(p))
     if (flags("inline") && flags("macro")) log.error("Macro and inline exclude each other", Some(p))
-    if (flags("interrupt") && returnType != "void") log.error("Interrupt function `$name` has to return void", Some(p))
-    if (addr.isEmpty && statements.isEmpty) log.error("Extern function `$name` must have an address", Some(p))
-    if (addr.isDefined && alignment.isDefined) log.error("Function `$name` has both address and alignment", Some(p))
-    if (statements.isEmpty && alignment.isDefined) log.error("Extern function `$name` cannot have alignment", Some(p))
-    if (statements.isEmpty && !flags("asm") && params.nonEmpty) log.error("Extern non-asm function `$name` cannot have parameters", Some(p))
+    if (flags("interrupt") && returnType != "void") log.error(s"Interrupt function `$name` has to return void", Some(p))
+    if (addr.isEmpty && statements.isEmpty) log.error(s"Extern function `$name` must have an address", Some(p))
+    if (addr.isDefined && alignment.isDefined) log.error(s"Function `$name` has both address and alignment", Some(p))
+    if (statements.isEmpty && alignment.isDefined) log.error(s"Extern function `$name` cannot have alignment", Some(p))
+    if (statements.isEmpty && !flags("asm") && params.nonEmpty) log.error(s"Extern non-asm function `$name` cannot have parameters", Some(p))
     if (flags("asm")) validateAsmFunctionBody(p, flags, name, statements)
     Seq(FunctionDeclarationStatement(name, returnType, params.toList,
       bank,