wl_proxy_marshal_flags causing build to fail

[svenssonjoel]

Hello.

I end up with this error (below). Is there some tag I can checkout that does not have this problem? I am trying to build 32bit.
Thank you and have a great day !

error: ‘wl_proxy_marshal_flags’ undeclared (first use in this function); did you mean ‘wl_proxy_marshal_array’?
88 | SDL_WAYLAND_SYM(struct wl_proxy*, wl_proxy_marshal_flags, (struct wl_proxy *proxy, uint32_t opcode, const struct wl_interface *interfac, uint32_t version, uint32_t flags, ...))
| ^~~~~~~~~~~~~~~~~~~~~~

[flibitijibibo]

Might be in the same vein as #5088. Any and all information about the build system and the configuration process will help!

[flibitijibibo]

See also #4636

[svenssonjoel]

I run a pretty basic Ubuntu install:
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.3 LTS
Release: 20.04
Codename: focal

gcc (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0
g++ (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0

The only special thing I am after is that I want to build SDL to 32bit binaries. And this is what seems to cause the breakage.
It seems to build perfectly fine as x86-64. So

> ./configure
> make 

Works fine. while

> CC="gcc -m32" ./configure
> CC="gcc -m32" make 

ends up in the wayland error. Maybe this is more about the wayland setup than about the SDL code... If I build SDL without any wayland support, will it still be a useful graphics library? I mean that it can output stuff to a window or so?

If there are some specific commands you want me to execute and provide the result of, I would love to be of assistance.
Thanks and have a great day.

[svenssonjoel]

Configure like this and it builds 32bit binaries!

CC="gcc -m32" ./configure --enable-video-wayland=no --enable-video-wayland-qt-touch=no --enable-wayland-shared=no

None of the tests work though. They just say: INFO: Couldn't initialize video driver: No available video device

[smcv]

The problem here is that when you build with a newer version of libwayland, the generated code includes calls to wl_proxy_marshal_flags(), but when you build with an older version of libwayland, that function isn't declared in the headers.

One way to resolve this is to disable Wayland video support (as you did in #5376 (comment)) and use X11 for graphics.

Another way to resolve this is to load Wayland libraries dynamically at runtime, instead of linking them as a hard dependency in the normal way: configure with --enable-wayland-shared.

If the SDL maintainers are interested in having SDL compile successfully with --disable-wayland-shared and a slightly older version of SDL, I applied a patch in Debian that avoids this issue. I'd intended it to be a short-term workaround (at the time, I was waiting for the Wayland library in Debian to be updated) but it could equally well go upstream if there's interest.

[flibitijibibo]

I'd apply that in upstream, sure - I believe it will also work for the dynamic link issue as well once the minimum is raised to 1.18.

[smcv]

I'd apply that in upstream, sure - I believe it will also work for the dynamic link issue as well once the minimum is raised to 1.18.

→ #5436 (not tested in its current form yet, but it worked when I packaged 2.0.20)