Unable to compile project with clang++ lto

[RageCPP]

/usr/local/bin/clang++ -fuse-ld=gold -flto -std=c++2a -Wpedantic -Wall -Wextra -Wsign-conversion -Wconversion /home/teo/Code/code_timer_backend/src/*.cpp /home/teo/Code/code_timer_backend/uSockets/*.o -o /home/teo/Code/code_timer_backend/build/main -DUWS_NO_ZLIB -I/usr/local/include/uWebSockets -I/home/teo/Code/code_timer_backend/uSockets/src

---

Error message：
/home/teo/Code/code_timer_backend/uSockets/bsd.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/bsd.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/context.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/context.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/epoll_kqueue.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/epoll_kqueue.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/gcd.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/gcd.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/libuv.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/libuv.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/loop.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/loop.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/openssl.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/openssl.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/quic.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/quic.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/socket.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/socket.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/udp.o: plugin needed to handle lto object /home/teo/Code/code_timer_backend/uSockets/udp.o: plugin needed to handle lto object /usr/lib/gcc/x86_64-linux-gnu/11/crtendS.o: plugin needed to handle lto object /tmp/lto-llvm-e7688f.o: plugin needed to handle lto object /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::HttpContext<true>::free(): error: undefined reference to 'us_socket_context_free' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::removePostHandler(void*): error: undefined reference to 'us_loop_ext' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::removePreHandler(void*): error: undefined reference to 'us_loop_ext' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::create(void*): error: undefined reference to 'us_create_loop' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::create(void*): error: undefined reference to 'us_loop_ext' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::create(void*): error: undefined reference to 'us_create_timer' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::create(void*): error: undefined reference to 'us_timer_ext' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::create(void*): error: undefined reference to 'us_timer_set' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::wakeupCb(us_loop_t*): error: undefined reference to 'us_loop_ext' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::create(void*)::{lambda(us_timer_t*)#1}::operator()(us_timer_t*) const: error: undefined reference to 'us_timer_ext' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::free(): error: undefined reference to 'us_timer_close' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::free(): error: undefined reference to 'us_loop_free' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::HttpContext<true>::getSocketContextData(): error: undefined reference to 'us_socket_context_ext' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::Loop::run(): error: undefined reference to 'us_loop_run' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::HttpContext<true>::listen(char const*, int, int): error: undefined reference to 'us_socket_context_listen' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::AsyncSocket<true>::write(char const*, int, bool, int): error: undefined reference to 'us_socket_is_closed' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::AsyncSocket<true>::write(char const*, int, bool, int): error: undefined reference to 'us_socket_write' /tmp/lto-llvm-e7688f.o:ld-temp.o:function uWS::AsyncSocket<true>::write(char const*, int, bool, int): error: undefined reference to 'us_socket_write'

[RageCPP]

The cause of the error may have been found, here is an example I used to illustrate

➜  lto-test gcc -flto main.c -c -o main.o
➜  lto-test ar q main.a main.o
ar: creating main.a
➜  lto-test gcc b.c -c -o b.o 
➜  lto-test gcc -flto main.a b.o -o main 
➜  lto-test ./main 
Foo2
➜  lto-test clang -flto a.a b.o -o main
clang-15: error: no such file or directory: 'a.a'
➜  lto-test clang -flto main.a b.o -o main
/usr/bin/ld: main.a(main.o): plugin needed to handle lto object
/usr/bin/ld: main.a(main.o): plugin needed to handle lto object
/usr/bin/ld: /lib/x86_64-linux-gnu/Scrt1.o: in function `_start':
(.text+0x1b): undefined reference to `main'
/usr/bin/ld: b.o: in function `foo1':
b.c:(.text+0x9): undefined reference to `foo2'
clang-15: error: linker command failed with exit code 1 (use -v to see invocation)