fn addFlag(gpa: Allocator, args: *std.ArrayList([]const u8), comptime name: []const u8, opt: ?bool) !void
fn addFlag(gpa: Allocator, args: *std.ArrayList([]const u8), comptime name: []const u8, opt: ?bool) !void { const cond = opt orelse return; try args.append(gpa, if (cond) "-f" ++ name else "-fno-" ++ name); }