If it’s in the language spec as required there and I’m using a compiler that claims to implement that language spec, I want the compiler to raise the error. Ad

If it’s in the language spec as required there and I’m using a compiler that claims to implement that language spec, I want the compiler to raise the error. Additionally offering help on how to fix it is welcome, but silently accepting not-language-X code as if it were valid language-X code is not what I want in a language-X compiler.