Panic on union Type Assertion

[dozn]

Context

package main
main :: proc() {
    x: U = []int{0}
    _ = x.([]int)
}
U :: union { []int }

Expected Behavior

No panic.

Current Behavior

Odin\src\llvm_backend_expr.cpp(3693): Panic: TODO(bill): type assertion []int

Notes

• Does not panic using []int{}, only panics when numbers are present there

---

Odin: dev-2025-02:0683a3d67
OS: Windows 11 Professional (version: 23H2), build 22631.4751
CPU: AMD Ryzen 7 3700X 8-Core Processor
RAM: 65457 MiB
Backend: LLVM 18.1.8

[Creativty]

For any one hunting the isssue, I found out that doing prevents the panic from happening:

package bug

U :: union { []int }

main :: proc() {
	x: U
	x   = []int{ 0 }
	_   = x.([]int)
}

This leads me to think that maybe the type of x is not being evaluated accurately, where the compiler thinks x is of type []int when it is of type U, thus panicking while union type asserting on a slice ?