Custom-Allocator

Fix E0742: alloc_error_handler Must Be in Main Crate

Rust intermediate Linux macOS Windows Aug 1, 2026

Rust compiler error E0742 occurs when #[alloc_error_handler] is placed on a function outside the main crate, violating the requirement that allocator functions must be defined in the entry crate.

Fix E0378: GlobalAlloc Implementation Error in Rust

Rust intermediate Linux macOS Windows WebAssembly Jul 30, 2026

Comprehensive guide to resolving Rust compiler error E0378, which occurs when implementing the GlobalAlloc trait with incorrect method signatures, conflicting implementations, or insufficient trait coverage.