Unable to install on Mac OS 10.14.6

[stevenvar]

Hi,

I'm unable to install the package on MacOS 10.14 (Mojave), while it did work when graphics was bundled with ocaml.

Here is the error:

src/unix/libgraph.h:17:10: fatal error: 'X11/Xlib.h' file not found
#include <X11/Xlib.h>

I have xquartz installed.

Doing a

sudo ln -s /opt/X11/include/X11 /usr/local/include/X11

(as mentioned here) just changes the error to:

ld: library not found for -lX11
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Any idea?

Thanks

[shenlebantongying]

Same thing will occur under macOS Catalina 10.15.1 with XQuartz installed.

Sorry, I do not quite understand OCaml's build system, but I can provide any further information to help.

[nojb]

Did you try doing

export LIBRARY_PATH=/opt/X11/lib

?

[shenlebantongying]

It works!

Thanks!

[nojb]

For info, LIBRARY_PATH is a PATH-like variable that is used to extend the list of directories where the compiler (gcc or similar) looks for static and shared variables at link-time. It is equivalent to adding those directories using an -L flag. As the location of libX11 is nonstandard on OS X the location of the library needs to be passed somehow to the compiler, which one can do using this environment variable, without need to modify the graphics build instructions.

[dra27]

That said, @nojb - presumably OCaml's configure script figured this out before (on the "just work" principle) - is it just that we're missing some logic in the conversion to Dune?

[stevenvar]

Just confirming that the

export LIBRARY_PATH=/opt/X11/lib

line works. Thanks!

[shindere]

David Allsopp (2019/12/05 01:35 -0800):

That said, @nojb - presumably OCaml's `configure` script figured this out before (on the "just work" principle) - is it just that we're missing some logic in the conversion to Dune?

It might be the case that I didn't implement looking in several directories for the graphics library, sorry about that.

[dra27]

@shindere - it's OK, the report suggests that this did work when the graphics library was in OCaml! I think AC_PATH_X was doing everything needed - the problem now for 4.09+ is that the Dune configuration system is not doing enough, and I wonder if we should fix that.

[dra27]

(I think we should fix it, because the graphics library's principal use remains in teaching, where it's very annoying to have extra steps for getting it working...)

[shindere]

David Allsopp (2019/12/05 02:07 -0800):

(I think we should fix it, because the graphics library's principal use remains in teaching, where it's very annoying to have extra steps for getting it working...)

I agree. It's just that we need to figure out who "we" is :)

[shenlebantongying]

I think the problem can be traced back to the https://github.com/ocaml/opam-repository/blob/master/packages/conf-libX11/conf-libX11.1/opam, where

[ "sh" "-exc" """PKG_CONFIG_PATH="$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig:/opt/X11/lib/pkgconfig" pkg-config --libs x11""" ] {os = "macos"}
After setting the PKG_CONFIG_PATH, the pkg-config still cannot identify --libs x11.

I don't know how to modified it and recompile graphics locally :(

[ghost]

@ZhengchaoJiang could you look if you have a file x11.pc on your system?

If it's just a missing pkg-config path, I guess we can add it to conf-libX11 and also add a dune-configurator program in graphics to get the flags from pkg-config

[shindere]

Please, when you include textual content, as much as possible it would be better to include the textual content itself rather than a screen shot. This is useful for blind persons like me and also for search engines (there is a joke that says that the most well known blind user of the web is Google).

[shenlebantongying]

Ok, I am a noob here anyway:)

i tried to add the line below to my .zshrc

export PKG_CONFIG_PATH="$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig:/opt/X11/lib/pkgconfig"

then from my terminal

pkg-config --list-all | grep x11                                                                                                   
x11-xcb               X11 XCB - X Library XCB interface
x11                   X11 - X Library

the X11 can be detected.

[ghost]

I setup the build to use dune-configurator, @ZhengchaoJiang could you give #17 a try?

[stevenvar]

#17 does not seem to fix it for me. I still get the following linker error

dune build
ocamlmklib src/dllgraphics_stubs.so,src/libgraphics_stubs.a (exit 2)
(cd _build/default && /Users/sv281/.opam/4.08.1/bin/ocamlmklib.opt -g -o src/graphics_stubs src/color.o src/draw.o src/dump_img.o src/events.o src/fill.o src/image.o src/make_img.o src/open.o src/point_col.o src/sound.o src/subwindow.o src/text.o -lX11)
ld: library not found for -lX11
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [default] Error 1

[shenlebantongying]

I changed to your branch locally, it still not working

dune build                                                                                                  [6:54:04]
  ocamlmklib src/dllgraphics_stubs.so,src/libgraphics_stubs.a (exit 2)
(cd _build/default && /Users/Bash/.opam/4.09.0/bin/ocamlmklib.opt -g -o src/graphics_stubs src/color.o src/draw.o src/dump_img.o src/events.o src/fill.o src/image.o src/make_img.o src/open.o src/point_col.o src/sound.o src/subwindow.o src/text.o -lX11)
ld: library not found for -lX11
clang: error: linker command failed with exit code 1 (use -v to see invocation)

[ghost]

could you provide the result of the following commands?

$ export PKG_CONFIG_PATH="$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig:/opt/X11/lib/pkgconfig"
$ pkg-config --cflags x11
$ pkg-config --libs x11

[ghost]

and also: uname -s (just to be sure)

[stevenvar]

Here you go :

$ export PKG_CONFIG_PATH="$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig:/opt/X11/lib/pkgconfig"
$ pkg-config --cflags x11
-I/opt/X11/include
$ pkg-config --libs x11
-L/opt/X11/lib -lX11
$ uname -s
Darwin

[ghost]

@stevenvar thanks. From the build error you reported in your previous message, it seems that the flags are not being obtained from pkg-config in src/discover/discover.ml. Could you add a couple of printfs in the from_pkg_config function in this file to see what's going on?

[stevenvar]

Ok what's happening is that the second match returns a None:

let from_pkg_config c =
  Printf.printf "entering";
  let fallback = ([], [ "-lX11" ]) in
  match C.Pkg_config.get c with
  | None -> fallback
  | Some pc -> (
      match C.Pkg_config.query pc ~package:"x11" with
      | None -> Printf.printf "fallback"; fallback
      | Some { cflags; libs } -> (cflags, libs) )

prints "fallback"

[stevenvar]

The other seemingly wrong thing is that the "match os c" in the entry point of the file returns Other

[ghost]

Ok, so os c returning Other is probably the issue. Could you provide the output of:

$ dune exec -- src/discover/discover.exe -verbose

?

[stevenvar]

Sure thing. Here you go:

run: /Users/sv281/.opam/default/bin/ocamlc.opt -config
-> process exited with code 0
-> stdout:
 | version: 4.09.0
 | standard_library_default: /Users/sv281/.opam/default/lib/ocaml
 | standard_library: /Users/sv281/.opam/default/lib/ocaml
 | ccomp_type: cc
 | c_compiler: cc
 | ocamlc_cflags: -O2 -fno-strict-aliasing -fwrapv 
 | ocamlc_cppflags: -D_FILE_OFFSET_BITS=64 -D_REENTRANT
 | ocamlopt_cflags: -O2 -fno-strict-aliasing -fwrapv
 | ocamlopt_cppflags: -D_FILE_OFFSET_BITS=64 -D_REENTRANT
 | bytecomp_c_compiler: cc -O2 -fno-strict-aliasing -fwrapv  -D_FILE_OFFSET_BITS=64 -D_REENTRANT
 | native_c_compiler: cc -O2 -fno-strict-aliasing -fwrapv -D_FILE_OFFSET_BITS=64 -D_REENTRANT
 | bytecomp_c_libraries: -lm  -lpthread 
 | native_c_libraries: -lm 
 | native_pack_linker: ld -r -o 
 | ranlib: ranlib
 | architecture: amd64
 | model: default
 | int_size: 63
 | word_size: 64
 | system: macosx
 | asm: clang -arch x86_64 -Wno-trigraphs -c
 | asm_cfi_supported: true
 | with_frame_pointers: false
 | ext_exe: 
 | ext_obj: .o
 | ext_asm: .s
 | ext_lib: .a
 | ext_dll: .so
 | os_type: Unix
 | default_executable_name: a.out
 | systhread_supported: true
 | host: x86_64-apple-darwin18.7.0
 | target: x86_64-apple-darwin18.7.0
 | flambda: false
 | spacetime: false
 | safe_string: false
 | default_safe_string: true
 | flat_float_array: true
 | afl_instrument: false
 | windows_unicode: false
 | supports_shared_libraries: true
 | exec_magic_number: Caml1999X026
 | cmi_magic_number: Caml1999I026
 | cmo_magic_number: Caml1999O026
 | cma_magic_number: Caml1999A026
 | cmx_magic_number: Caml1999Y026
 | cmxa_magic_number: Caml1999Z026
 | ast_impl_magic_number: Caml1999M026
 | ast_intf_magic_number: Caml1999N026
 | cmxs_magic_number: Caml1999D026
 | cmt_magic_number: Caml1999T026
-> stderr:
run: uname -s
-> process exited with code 0
-> stdout:
 | Darwin
-> stderr:
which: pkg-config
-> found: /usr/local/bin/pkg-config
which: brew
-> found: /usr/local/bin/brew
run: /usr/local/bin/brew --prefix
-> process exited with code 0
-> stdout:
 | /usr/local
-> stderr:
run: /usr/local/bin/pkg-config --print-errors x11
-> process exited with code 1
-> stdout:
-> stderr:
 | Package x11 was not found in the pkg-config search path.
 | Perhaps you should add the directory containing `x11.pc'
 | to the PKG_CONFIG_PATH environment variable
 | No package 'x11' found

EDIT: accidentally ran it with ocaml 4.08.1. I corrected it but the same happens with 4.09

[stevenvar]

Ok I think I found the problem.

For some reason running uname -s in the "os" function returns the stdout "Darwin\n" and not "Darwin"

When changing the line

 | { exit_code = 0; stdout = "Darwin"; _ } -> Darwin

to

 | { exit_code = 0; stdout = "Darwin\n"; _ } -> Darwin

Everything seems to work.

[ghost]

ah, yes of course I forgot to trim the output 🤦‍♂️

I changed the code in #17 to trim the output. If you could do a final test to confirm it works as expected, I'll merge and prepare a new release. Thanks

[stevenvar]

Yes that works! thanks

[ghost]

Cool, merging :)

[ghost]

and releasing: ocaml/opam-repository#15455

[garrigue]

Completely unrelated: in my mail, your emoticon get displayed as🤦‍ ♂
I.e. "man hitting forehead" = "woman hitting forehead + male"
Mysteries of unicode.

By the way, I had the same problem, and this release fixes it for me too.
(I'm using MacOS 10.15.1, but with macports rather than brew)

[ghost]

Haha, and I actually typed :man_facepalming:!

Glad it fixes the issue for you too Jacques!

[dra27]

@garrigue - that's correct. "man facepalming" is a sequence of characters, it means your MUA isn't processing the zero-width-joiners correctly (see here). The "person facepalming" emoji is permitted to have the appearance of any gender (as you can see on that page). Skin-tone and various other glyphs are selected this way via sequences.