Derive on ErrorVault — Developer Error Code Dictionary

Fix E0615: Attempted to Derive an Impl of a Trait That Is Not Derivable

Sun, 26 Jul 2026 10:20:04 +0800

1. Symptoms

When you encounter Rust error E0615, the compiler produces output similar to the following:

error[E0615]: attempted to derive an impl of a trait that is not marked `#[derivable]`
  --> src/main.rs:5:12
   |
5  | #[derive(MyCustomTrait)]
   |            ^^^^^^^^^^^^^
   |
   = note: only traits marked with `#[derivable]` can be derived

The error manifests at the specific line where the #[derive(...)] attribute is applied to a struct or enum definition. The compiler rejects the derivation request because the specified trait is not recognized as derivable by the Rust compiler’s built-in derive mechanism. This error typically surfaces during the compilation phase when the compiler attempts to expand the derive macro and discovers that the target trait lacks the necessary metadata to support automatic implementation generation.

Fix E0367: Malformed Attribute Syntax in Rust

Wed, 22 Jul 2026 03:08:04 +0800

1. Symptoms

When the Rust compiler encounters a malformed attribute, it halts compilation and emits error E0367. This error manifests with several observable indicators that help developers identify the problematic code location.

The compiler output typically includes the error code, a descriptive message, and a span pointing to the offending attribute. The error message generally reads “malformed attribute attribute, expected (” or a similar variant indicating the expected syntax structure.

Fix E0732: #[derive] on Enum with No Variants

Wed, 20 May 2026 17:32:04 +0800

1. Symptoms

When attempting to compile Rust code that uses the #[derive] attribute on an enum with zero variants, the compiler produces the E0732 error:

error[E0732]: #[derive] can't be used with enum that has no data
  --> src/main.rs:3:1
   |
3  | #[derive(Debug, Clone)]
   | ^^^^^^^^^^^^^^^^^^^^^^
4  | enum Void {}
   | ---------- has no variants

The error manifests with any trait in the derive macro, whether it’s Debug, Clone, Default, PartialEq, or any other derive-able trait. The compiler will also highlight the enum definition itself as having no variants.