exception Dl.DL_error : undefined symbol: SDL_GetError

Question

所以，我想使用 Tsdl，这就是我所做的：

我找不到 SDL 2.0.5 和 apt-get 所以我下载了它，./configure && make && sudo make install
opam install tsdl

然后我创建了一个文件 main.ml（在 tsdl website 上作为示例给出）：

open Tsdl
open Result

let main () = match Sdl.init Sdl.Init.video with
  | Error (`Msg e) -> Sdl.log "Init error: %s" e; exit 1
  | Ok () ->
    match Sdl.create_window ~w:640 ~h:480 "SDL OpenGL" Sdl.Window.opengl with
     | Error (`Msg e) -> Sdl.log "Create window error: %s" e; exit 1
     | Ok w ->
       Sdl.delay 3000l;
       Sdl.destroy_window w;
       Sdl.quit ();
       exit 0

let () = main ()

ocamlfind ocamlopt -package tsdl -linkpkg -o main.native main.ml

它有效，现在我的问题来了：

./main.native
Fatal error: exception Dl.DL_error("./main.native: undefined symbol: SDL_GetError")

我是不是做错了什么，或者我是否需要明确告诉我的 SDL2 库在哪里或其他什么地方？

更新：

> ocamlobjinfo $(opam config var tsdl:lib)/tsdl.cmxa | grep Extra
Extra C object files: -L/usr/local/lib -Wl,-rpath,/usr/local/lib -Wl,--enable-new-dtags -lSDL2 -ltsdl
Extra C options:

> sdl2-config --libs
-L/usr/local/lib -Wl,-rpath,/usr/local/lib -Wl,--enable-new-dtags -lSDL2

更新 2：

> ldd ./main.native 
    linux-vdso.so.1 =>  (0x00007fff1f4c1000)
    libffi.so.6 => /usr/lib/x86_64-linux-gnu/libffi.so.6 (0x00007f4aff55e000)
    libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f4aff255000)
    libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f4aff050000)
    libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f4afec87000)
    /lib64/ld-linux-x86-64.so.2 (0x000055dc05e17000)

更新 3

lhooq@lhooq ~/tsdl $ ocamlfind ocamlopt -cclib -lSDL2 -package tsdl -linkpkg -o min.native min.ml -verbose

Effective set of compiler predicates: pkg_result,pkg_unix,pkg_bigarray,pkg_str,pkg_bytes,pkg_ctypes,pkg_ctypes.foreign.base,pkg_ctypes.foreign.unthreaded,pkg_ctypes.foreign,pkg_tsdl,autolink,native
+ ocamlopt.opt -o min.native -verbose -I /home/lhooq/.opam/4.04.0/lib/result -I /home/lhooq/.opam/4.04.0/lib/bytes -I /home/lhooq/.opam/4.04.0/lib/ctypes -I /home/lhooq/.opam/4.04.0/lib/tsdl /home/lhooq/.opam/4.04.0/lib/result/result.cmxa /home/lhooq/.opam/4.04.0/lib/ocaml/unix.cmxa /home/lhooq/.opam/4.04.0/lib/ocaml/bigarray.cmxa /home/lhooq/.opam/4.04.0/lib/ocaml/str.cmxa /home/lhooq/.opam/4.04.0/lib/ctypes/ctypes.cmxa /home/lhooq/.opam/4.04.0/lib/ctypes/ctypes-foreign-base.cmxa /home/lhooq/.opam/4.04.0/lib/ctypes/ctypes-foreign-unthreaded.cmxa /home/lhooq/.opam/4.04.0/lib/tsdl/tsdl.cmxa -cclib -lSDL2 min.ml
+ as -o 'min.o' '/tmp/camlasm9ab424.s'
+ as -o '/tmp/camlstartupe796c9.o' '/tmp/camlstartup4a1081.s'
+ gcc -o 'min.native'   '-L/home/lhooq/.opam/4.04.0/lib/result' '-L/home/lhooq/.opam/4.04.0/lib/bytes' '-L/home/lhooq/.opam/4.04.0/lib/ctypes' '-L/home/lhooq/.opam/4.04.0/lib/tsdl' '-L/home/lhooq/.opam/4.04.0/lib/ocaml'  '/tmp/camlstartupe796c9.o' '/home/lhooq/.opam/4.04.0/lib/ocaml/std_exit.o' 'min.o' '/home/lhooq/.opam/4.04.0/lib/tsdl/tsdl.a' '/home/lhooq/.opam/4.04.0/lib/ctypes/ctypes-foreign-unthreaded.a' '/home/lhooq/.opam/4.04.0/lib/ctypes/ctypes-foreign-base.a' '/home/lhooq/.opam/4.04.0/lib/ctypes/ctypes.a' '/home/lhooq/.opam/4.04.0/lib/ocaml/str.a' '/home/lhooq/.opam/4.04.0/lib/ocaml/bigarray.a' '/home/lhooq/.opam/4.04.0/lib/ocaml/unix.a' '/home/lhooq/.opam/4.04.0/lib/result/result.a' '/home/lhooq/.opam/4.04.0/lib/ocaml/stdlib.a' '-L/usr/local/lib' '-Wl,-rpath,/usr/local/lib' '-Wl,--enable-new-dtags' '-lSDL2' '-ltsdl' '-Wl,--no-as-needed' '-lffi' '-lctypes-foreign-base_stubs' '-Wl,--no-as-needed' '-lffi' '-lctypes_stubs' '-Wl,--no-as-needed' '-lcamlstr' '-lbigarray' '-lunix' '-lSDL2' '/home/lhooq/.opam/4.04.0/lib/ocaml/libasmrun.a' -lm  -ldl

lhooq@lhooq ~/tsdl $ ocamlfind ocamlopt -package tsdl -linkpkg -o min.native min.ml -verbose

Effective set of compiler predicates: pkg_result,pkg_unix,pkg_bigarray,pkg_str,pkg_bytes,pkg_ctypes,pkg_ctypes.foreign.base,pkg_ctypes.foreign.unthreaded,pkg_ctypes.foreign,pkg_tsdl,autolink,native
+ ocamlopt.opt -o min.native -verbose -I /home/lhooq/.opam/4.04.0/lib/result -I /home/lhooq/.opam/4.04.0/lib/bytes -I /home/lhooq/.opam/4.04.0/lib/ctypes -I /home/lhooq/.opam/4.04.0/lib/tsdl /home/lhooq/.opam/4.04.0/lib/result/result.cmxa /home/lhooq/.opam/4.04.0/lib/ocaml/unix.cmxa /home/lhooq/.opam/4.04.0/lib/ocaml/bigarray.cmxa /home/lhooq/.opam/4.04.0/lib/ocaml/str.cmxa /home/lhooq/.opam/4.04.0/lib/ctypes/ctypes.cmxa /home/lhooq/.opam/4.04.0/lib/ctypes/ctypes-foreign-base.cmxa /home/lhooq/.opam/4.04.0/lib/ctypes/ctypes-foreign-unthreaded.cmxa /home/lhooq/.opam/4.04.0/lib/tsdl/tsdl.cmxa min.ml
+ as -o 'min.o' '/tmp/camlasm201bd8.s'
+ as -o '/tmp/camlstartup7113e2.o' '/tmp/camlstartup4724f2.s'
+ gcc -o 'min.native'   '-L/home/lhooq/.opam/4.04.0/lib/result' '-L/home/lhooq/.opam/4.04.0/lib/bytes' '-L/home/lhooq/.opam/4.04.0/lib/ctypes' '-L/home/lhooq/.opam/4.04.0/lib/tsdl' '-L/home/lhooq/.opam/4.04.0/lib/ocaml'  '/tmp/camlstartup7113e2.o' '/home/lhooq/.opam/4.04.0/lib/ocaml/std_exit.o' 'min.o' '/home/lhooq/.opam/4.04.0/lib/tsdl/tsdl.a' '/home/lhooq/.opam/4.04.0/lib/ctypes/ctypes-foreign-unthreaded.a' '/home/lhooq/.opam/4.04.0/lib/ctypes/ctypes-foreign-base.a' '/home/lhooq/.opam/4.04.0/lib/ctypes/ctypes.a' '/home/lhooq/.opam/4.04.0/lib/ocaml/str.a' '/home/lhooq/.opam/4.04.0/lib/ocaml/bigarray.a' '/home/lhooq/.opam/4.04.0/lib/ocaml/unix.a' '/home/lhooq/.opam/4.04.0/lib/result/result.a' '/home/lhooq/.opam/4.04.0/lib/ocaml/stdlib.a' '-L/usr/local/lib' '-Wl,-rpath,/usr/local/lib' '-Wl,--enable-new-dtags' '-lSDL2' '-ltsdl' '-Wl,--no-as-needed' '-lffi' '-lctypes-foreign-base_stubs' '-Wl,--no-as-needed' '-lffi' '-lctypes_stubs' '-Wl,--no-as-needed' '-lcamlstr' '-lbigarray' '-lunix' '/home/lhooq/.opam/4.04.0/lib/ocaml/libasmrun.a' -lm  -ldl

Answer 1

这似乎是 tsdl 中的一个小问题，有关详细信息，请参阅：https://github.com/dbuenzli/tsdl/issues/38

在master中是固定的。正如作者建议的那样，您可以（暂时）将此作为临时修复：

opam pin add tsdl --dev

编辑：正如下面@dbuenzli 所指出的，这已在 0.9.4 中得到修复，该版本正在走向 opam。

exception Dl.DL_error : undefined symbol: SDL_GetError

exception Dl.DL_error : undefined symbol: SDL_GetError

binding

ocaml

sdl-2