Creating bit field using non-constant variables breaking code gen

[jockus]

Context

Creating bit field using non-constant variables causing a code gen failure.

package main

Foo :: bit_field u32 {
	val : int | 10,
}

main :: proc() {
	foo : Foo

	foo = Foo{val = 1}

	a :: 5
	foo = Foo{val = a}

	b := 5
	foo = Foo{val = b} // code gen failure
}

• Operating System & Odin Version:
  Odin: dev-2024-05
  OS: Windows 10 Enterprise
  Backend: LLVM 17.0.1

Expected Behavior

No code gen failure.

Current Behavior

Code gen failure

Failure Information (for bugs)

Steps to Reproduce

Please provide detailed steps for reproducing the issue.

1. Compile above code
2. See code gen failure

Failure Logs

|| [build.bat]
|| LLVM CODE GEN FAILED FOR PROCEDURE: main.main
|| define internal void @main.main(ptr noalias nocapture nonnull %__.context_ptr) {
|| decls:
||   %foo = alloca i32, align 4
||   %0 = alloca i32, align 4
||   %1 = alloca i32, align 4
||   %b = alloca i64, align 8
||   %2 = alloca i32, align 4
||   br label %entry
|| 
|| entry:                                            ; preds = %decls
||   store i32 0, ptr %foo, align 4
||   store i32 0, ptr %0, align 4
||   store i32 1, ptr %0, align 4
||   %3 = load i32, ptr %0, align 4
||   store i32 %3, ptr %foo, align 4
||   store i32 0, ptr %1, align 4
||   store i32 5, ptr %1, align 4
||   %4 = load i32, ptr %1, align 4
||   store i32 %4, ptr %foo, align 4
||   store i64 5, ptr %b, align 8
||   store i32 0, ptr %2, align 4
||   %5 = load i64, ptr %b, align 8
||   %6 = zext i64 %5 to i32
||   %7 = and i32 %6, 1023
||   %8 = shl i32 %7, 0
||   %9 = or i32 0, %8
||   store i32 %9, ptr %2, align 4
||   %10 = load i32, ptr %2, align 4
||   store i32 %10, ptr %foo, align 4
||   ret void
|| }
|| 
|| 
|| 
|| 
|| Type too small for ZExt
||   %6 = zext i64 %5 to i32
|| [Finished in 0 seconds with code 1]

[jockus]

This seems to specifically be the case when an individual field type is larger than the bit field type. val : int | 10 to val : u32 | 10 works fine.