Wxdemo crashes on gl tab (macos)

Questions / Help
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1

I am an erlang/Elixir newbee and playing with wx:demo() on the latest macos (15.5) it crashes with the below error when selecting the open gl demo:

1> wx:demo().
ok
=CRASH REPORT==== 29-Jun-2025::09:45:34.206778 ===
  crasher:
    initial call: ex_gl:init/1
    pid: <0.93.0>
    registered_name: []
    exception exit: {{nif_not_loaded,module,gl,line,356},
                     [{erlang,nif_error,
                              [{nif_not_loaded,module,gl,line,356}],
                              [{error_info,#{module => erl_erts_errors}}]},
                      {gl,nif_stub_error,1,[{file,"gen/gl.erl"},{line,321}]},

Looking at installing open GL in my mac, it appears to be deprecated in favor of another framework called Metal.

I wonder if we could detect that NIF is not available and provide an appropriate error message in the Wx demo (rather than crashing it).

Thanks,
Francisco

2

Nah, it probably means if couldn’t find the erl_gl.EXTENSION file below lib/wx-VSN/priv/ dir.

Do you have something like that?

3

I do have the erl_gl.so in wx-2.5/priv

➜  priv pwd
/Users/fgarau/.asdf/installs/erlang/28.0.1/lib/wx-2.5/priv
➜  priv ll
total 9672
-rw-r--r--@ 1 fgarau  staff   2.6K 13 Jun 15:54 erlang-logo64.png
-rw-r--r--@ 1 fgarau  staff   1.3K 13 Jun 15:54 erlang-logo32.png
-rw-r--r--@ 1 fgarau  staff   6.1K 13 Jun 15:54 erlang-logo128.png
-rwxr-xr-x@ 1 fgarau  staff   4.1M 28 Jun 17:02 wxe_driver.so
-rwxr-xr-x@ 1 fgarau  staff   592K 28 Jun 17:02 erl_gl.so
➜  priv
4

Ok that is strange, then it should work out of the box.

I expect other error printouts, this looks like the code didn’t even try to load erl_gl.so.

We had a bug in the RC candidates, that manifested it self like this.

How did you build erlang/OTP?

What does grep -r CAN_BUILD_DRIVER lib/wx/* (in the src tree) say?

5

I didn’t build erlang – I’ve installed it with the asdf package manager

➜ asdf list
elixir
  1.10.2-otp-22
  1.18.4
 *1.18.4-otp-28
erlang
 *28.0.1
nodejs
  10.16.3
  21.6.2
 *24.3.0
➜  pwd
/Users/fgarau/.asdf/installs/erlang
➜  grep -r CAN_BUILD_DRIVER lib/wx-2.5/*
lib/wx-2.5/src/gen/gl.erl:-ifdef(CAN_BUILD_DRIVER).
6

Thanks but the installed package is no good for debugging :slight_smile:

It looks like the erlang code is built with,
CAN_BUILD_DRIVER=false

But you clearly have the driver in priv dir.

Hmm I don’t know asdf builds but this looks strange.

You could test by recompile the gl.erl:

cd /Users/fgarau/.asdf/installs/erlang/lib/wx-2.5/src/
erlc -DCAN_BUILD_DRIVER=true -o ../ebin gen/gl.erl
7

Thanks! Now it works when gl is recompiled with any of the below commands:

erlc -DCAN_BUILD_DRIVER=true -o ../ebin gen/gl.erl
erlc -DCAN_BUILD_DRIVER=false -o ../ebin gen/gl.erl

and it crashes as before when recompiled as:

erlc -o ../ebin gen/gl.erl