Crystal: Module validation failed: Call parameter type does not match function signature!

[Blacksmoke16]

https://play.crystal-lang.org/#/r/8hb8

require "json"

class Parent
  def initialize(@data : String? = ""); end
end

class Child < Parent
  def initialize(data : _, convert : Bool = false)
    super convert ? data.to_json : data    
  end
end

pp Child.new 17

Module validation failed: Call parameter type does not match function signature!
  %16 = load %String, %String* %15, !dbg !12
 %String*  %17 = call %String* @"*Child@Parent#initialize<String>:String"(%Child* %self, %String %16), !dbg !15
 (Exception)
  from ???
  from ???
  from ???
  from ???
  from ???
  from ???
  from ???
  from main
  from __libc_start_main
  from _start
  from ???
Error: you've found a bug in the Crystal compiler. Please open an issue, including source code that will allow us to reproduce the bug: https://github.com/crystal-lang/crystal/issues

_Originally posted by @Blacksmoke16 in https://github.com/crystal-lang/crystal/issues/7279#issuecomment-580528807_

[asterite]

Reduced:

class Parent
  def initialize(@data : String)
  end
end

class Child < Parent
  def initialize
    super("" || 1)
  end
end

Child.new

[jhass]

Ah you were faster.

Trying to reduce I found the maybe related

class Parent
  def initialize(@data : Int32? = 0); end
end

class Child < Parent
  def initialize(data : _, convert : Bool = false)
    super convert ? data.unsafe_as(Int64) : data    
  end
end

Child.new 17

Module validation failed: Load operand must be a pointer.
  load void, i32 %15, !dbg !12
Call parameter type does not match function signature!
  load void, i32 %15, !dbg !12
 i32  %16 = call i32 @"*Child@Parent#initialize<Int32>:Int32"(%Child* %self, void <badref>), !dbg !15

[dorianmariefr]

i have the same error message, but with very different code:

Module validation failed: Call parameter type does not match function signature!
  %5 = load %String, %String* %4, !dbg !14
 %String*  call void @"*Crlox::Return@Exception#initialize<(String | Nil)>:Nil"(%"Crlox::Return"* %self, %String %5), !dbg !15
 (Exception)
  from raise<Exception>:NoReturn
  from raise<String>:NoReturn
  from Crystal::CodeGenVisitor#finish:Nil
  from Crystal::Compiler#codegen<Crystal::Program, Crystal::ASTNode+, Array(Crystal::Compiler::Source), String>:(Tuple(Array(Crystal::Compiler::CompilationUnit), Array(String)) | Nil)
  from Crystal::Compiler#compile<Array(Crystal::Compiler::Source), String>:Crystal::Compiler::Result
  from Crystal::Command#run_command<Bool>:Nil
  from Crystal::Command#run:(Bool | Nil)
  from __crystal_main
  from main
Error: you've found a bug in the Crystal compiler. Please open an issue, including source code that will allow us to reproduce the bug: https://github.com/crystal-lang/crystal/issues

full source code to reproduce.

and the last change i made was in to add Callable in interpreter.cr on the Return class:

+    @value : (LiteralType | Callable)
+
+    def initialize(value : (LiteralType | Callable))

[dorianmariefr]

fixed by calling super() instead of super in the initializer