核心功能，to_pb 序列化bug

[pimatrix]

问题：当struct的第一个字段int32_t test;被注释的情况下，才可以编译通过，否则报错

/usr/bin/gcc -c -m64 -fvisibility=hidden -fvisibility-inlines-hidden -O3 -std=c++20 -DNDEBUG -o build/.objs/hello/linux/x86_64/release/src/main.cpp.o src/main.cpp
error: In file included from /usr/local/include/iguana/pb_reader.hpp:3,
                 from /usr/local/include/ylt/struct_pb/struct_pb_impl.hpp:18,
                 from /usr/local/include/ylt/struct_pb.hpp:17,
                 from src/main.cpp:3:
/usr/local/include/iguana/pb_util.hpp: In instantiation of ‘void iguana::detail::append_varint_u32(Writer&, std::index_sequence<_Idx ...>) [with long unsigned int v = 130; Writer = iguana::memory_writer; long unsigned int ...I = {0}; std::index_sequence<_Idx ...> = std::integer_sequence<long unsigned int, 0>]’:
/usr/local/include/iguana/pb_util.hpp:206:23:   required from ‘void iguana::detail::serialize_varint_u32(Writer&) [with unsigned int v = 130; Writer = iguana::memory_writer]’
/usr/local/include/iguana/pb_writer.hpp:200:30:   required from ‘void iguana::detail::to_pb_impl(Type&&, uint32_t*&, Writer&) [with unsigned int key = 130; bool omit_default_val = true; Type = const std::__cxx11::basic_string<char>&; Writer = iguana::memory_writer; uint32_t = unsigned int]’
/usr/local/include/iguana/pb_writer.hpp:135:32:   required from ‘iguana::detail::to_pb_impl<0>(const input_t&, uint32_t*&, iguana::memory_writer&)::<lambda(auto:318)> [with auto:318 = std::integral_constant<long unsigned int, 15>]’
/usr/local/include/iguana/pb_util.hpp:338:22:   required from ‘constexpr void iguana::detail::for_each_n(F&&, std::index_sequence<__indices ...>) [with F = to_pb_impl<0>(const input_t&, uint32_t*&, iguana::memory_writer&)::<lambda(auto:318)>; long unsigned int ...I = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}; std::index_sequence<__indices ...> = std::integer_sequence<long unsigned int, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15>]’
/usr/local/include/iguana/pb_writer.hpp:114:15:   required from ‘void iguana::detail::to_pb_impl(Type&&, uint32_t*&, Writer&) [with unsigned int key = 0; bool omit_default_val = true; Type = const input_t&; Writer = iguana::memory_writer; uint32_t = unsigned int]’
/usr/local/include/iguana/pb_writer.hpp:482:26:   required from ‘void iguana::to_pb(const T&, Stream&) [with T = input_t; Stream = std::__cxx11::basic_string<char>; typename std::enable_if<(ylt_refletable_v<T> || is_custom_reflection_v<T>), int>::type <anonymous> = 0]’
src/main.cpp:32:18:   required from here
/usr/local/include/iguana/pb_util.hpp:200:61: error: invalid conversion from ‘uint8_t*’ {aka ‘unsigned char*’} to ‘const char*’ [-fpermissive]
  200 |   ((temp = static_cast<uint8_t>(v >> (7 * I)), writer.write(&temp, 1)), ...);
      |                                                             ^~~~~
      |                                                             |
      |                                                             uint8_t* {aka unsigned char*}
In file included from /usr/local/include/iguana/common.hpp:4,
                 from /usr/local/include/iguana/dynamic.hpp:2,
                 from /usr/local/include/ylt/struct_pb/struct_pb_impl.hpp:17:
/usr/local/include/iguana/util.hpp:200:26: note:   initializing argument 1 of ‘void iguana::memory_writer::write(const char*, std::size_t)’
  200 |   void write(const char* data, std::size_t len) {
      |              ~~~~~~~~~~~~^~~~

全部demo代码

#include <iostream>
#include <ylt/struct_pb.hpp>

struct input_t {
	int32_t test;
	int32_t test1;
	int32_t test2;
	std::string tf1;
	std::string tf2;
	std::string tf3;
	std::string tf4;
	int32_t tf5;
	int32_t tf6;
	std::string tf7;
	int32_t tf8;
	std::string tf9;
	std::string tf10;
	std::string tf11;
	std::string tf12;
	std::string tf13;
};

int main(int argc, char** argv) {

    // 模拟数据
    input_t data;
    data.tf13 = "test";

    // 序列化
    std::string ss;
    iguana::to_pb(data, ss);

    std::cout << ss << std::endl;
    std::cout << "hello world!" << std::endl;
    return 0;
}

[pimatrix]

由于缺少tag，我查了一下，对应的代码版本 d07ad5a

[qicosmos]

是一个编译错误，等pr #333 合并之后就可以了。