fn appendPlaceholder(astgen: *AstGen) Allocator.Error!Zir.Inst.Index
fn appendPlaceholder(astgen: *AstGen) Allocator.Error!Zir.Inst.Index { const inst: Zir.Inst.Index = @fromBackingInt(@intCast(astgen.instructions.len)); try astgen.instructions.append(astgen.gpa, .{ .tag = .extended, .data = .{ .extended = .{ .opcode = .value_placeholder, .small = undefined, .operand = undefined, } }, }); return inst; }