Package-level variable initialization order limits

Initialization Sequence in Complex Package Dependencies

Go manages package-level variable initialization and the execution of init() functions based on the dependency graph. While circular dependencies are prohibited at compile-time, the exact execution order of init() functions across multiple files within a single package can introduce uncertainty when global state is involved.

The primary constraint is ensuring that dependent variables are fully initialized before they are accessed by other package-level variables or initialization functions, especially when multiple files contribute to the same package state.

• Dependence on the lexical order of files during compilation.
• Potential for unpredictable state if init() functions rely on side effects from other files in the same package.

What is the deterministic behavior for the execution order of init() functions across multiple files within a single package? How does the compiler resolve initialization priorities for variables that depend on other package-level identifiers defined in different files?