Description of problem:
Hi,

I was investigating some graphical glitching for an SDL game (OpenRA) under FC24 under Wayland which doesn't show up under Xorg. When doing some SDL tests, I saw that SDL2 applications were still defaulting to "x11" under Wayland (if "lg" output and tests below are to be believed...). I'm running a fairly default FC24 install.

2 question/issues:
A) Does "SDL_Init( SDL_INIT_VIDEO )" still default to "x11" under Wayland?

The tests below show it is. Does this apply: https://wiki.archlinux.org/index.php/wayland#SDL and if so whats the plan around this transition? If the aim is to have Wayland be the default for FC25, should this be patched now for people testing Wayland in FC24 to flush out bugs?

B) Is "SDL_Init(SDL_INIT_VIDEO);" known to work for the Wayland SDL video driver?

It crashes for me, see below - maybe something more is needed for this patch: http://pkgs.fedoraproject.org/cgit/rpms/SDL2.git/tree/SDL2-wayland-dyn-wl_proxy_marshal_constructor_versioned.patch?id=fac91fa8fec7a8dc2f02008bd1eb43a6628f3932
Or maybe I am not linking this properly...

Thanks!



Version-Release number of selected component (if applicable):
$ rpm -qa SDL2
SDL2-2.0.4-4.fc24.x86_64

How reproducible:
All the time under Gnome + Wayland

Steps to Reproduce:


### Directly calling SDL_Init() shows this issue
[jman@talos test_sdl]$ cat test_sdl.c
#include <stdio.h>
#include <SDL.h>
int main( int argc, char *argv[] ) {
    if( SDL_Init( SDL_INIT_VIDEO ) < 0 ) {
        printf( "SDL_Init() error: %s\n", SDL_GetError() );
        return 1;
    }
    printf( "SDL_Init() succeeded.\n" );
    printf( "SDL_GetCurrentVideoDriver(): %s\n", SDL_GetCurrentVideoDriver() );
    return 0;
}

[jman@talos test_sdl]$ ./test_sdl 
SDL_Init() succeeded.
SDL_GetCurrentVideoDriver(): x11
[jman@talos test_sdl]$ SDL_VIDEODRIVER=x11 ./test_sdl
SDL_Init() succeeded.
SDL_GetCurrentVideoDriver(): x11
[jman@talos test_sdl]$ SDL_VIDEODRIVER=blabla ./test_sdl
SDL_Init() error: blabla not available
[jman@talos test_sdl]$ SDL_VIDEODRIVER=wayland ./test_sdl
Segmentation fault (core dumped)

### OpenArena just for comparison, not directly concerned about it at the moment...
### "lg" shows x11 windows by default
### crashes when wayland driver is chosen
[jman@talos test_sdl]$ openarena
[jman@talos test_sdl]$ SDL_VIDEODRIVER=wayland openarena
SDL_Init( SDL_INIT_VIDEO ) FAILED (No available video device)



[jman@talos test_sdl]$ SDL_VIDEODRIVER=wayland gdb ./test_sdl
GNU gdb (GDB) Fedora 7.11.1-75.fc24
[...skip...]
Reading symbols from ./test_sdl...done.
(gdb) run
Starting program: /home/jman/test_sdl/test_sdl 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".

Program received signal SIGSEGV, Segmentation fault.
0x0000000000000000 in ?? ()
(gdb) bt
#0  0x0000000000000000 in ?? ()
#1  0x00007ffff7b8fb4c in wl_registry_bind (version=1, interface=<optimized out>, name=<optimized out>, wl_registry=<optimized out>)
    at /usr/include/wayland-client-protocol.h:305
#2  display_handle_global (data=0x605490, registry=<optimized out>, id=<optimized out>, interface=<optimized out>, version=<optimized out>)
    at /usr/src/debug/SDL2-2.0.4/src/video/wayland/SDL_waylandvideo.c:246
#3  0x00007ffff367ac58 in ffi_call_unix64 () at ../src/x86/unix64.S:76
#4  0x00007ffff367a6ba in ffi_call (cif=cif@entry=0x7fffffffdbd0, fn=<optimized out>, rvalue=<optimized out>, rvalue@entry=0x0, avalue=avalue@entry=0x7fffffffdca0)
    at ../src/x86/ffi64.c:525
#5  0x00007ffff3885a9e in wl_closure_invoke (closure=closure@entry=0x6044d0, flags=flags@entry=1, target=<optimized out>, target@entry=0x604300, 
    opcode=opcode@entry=0, data=<optimized out>) at src/connection.c:949
#6  0x00007ffff3882840 in dispatch_event (display=display@entry=0x605520, queue=<optimized out>) at src/wayland-client.c:1274
#7  0x00007ffff3883a14 in dispatch_queue (queue=0x6055e8, display=0x605520) at src/wayland-client.c:1420
#8  wl_display_dispatch_queue_pending (display=0x605520, queue=0x6055e8) at src/wayland-client.c:1662
#9  0x00007ffff3883d2f in wl_display_roundtrip_queue (display=0x605520, queue=0x6055e8) at src/wayland-client.c:1085
#10 0x00007ffff7b8f824 in Wayland_VideoInit (_this=<optimized out>) at /usr/src/debug/SDL2-2.0.4/src/video/wayland/SDL_waylandvideo.c:299
#11 0x00007ffff7b7a50c in SDL_VideoInit_REAL (driver_name=<optimized out>, driver_name@entry=0x0) at /usr/src/debug/SDL2-2.0.4/src/video/SDL_video.c:513
#12 0x00007ffff7ae2587 in SDL_InitSubSystem_REAL (flags=16416) at /usr/src/debug/SDL2-2.0.4/src/SDL.c:173
#13 0x000000000040078f in main (argc=1, argv=0x7fffffffdfa8) at test_sdl.c:4

###
### "WAYLAND_wl_proxy_marshal_constructor_versioned" an uninitialzed pointer/hook?
###
(gdb) frame 1
#1  0x00007ffff7b8fb4c in wl_registry_bind (version=1, interface=<optimized out>, name=<optimized out>, wl_registry=<optimized out>)
    at /usr/include/wayland-client-protocol.h:305
305		id = wl_proxy_marshal_constructor_versioned((struct wl_proxy *) wl_registry,
(gdb) print wl_proxy_marshal_constructor_versioned
$1 = {struct wl_proxy *(struct wl_proxy *, uint32_t, const struct wl_interface *, uint32_t, ...)} 0x7ffff3882eb0 <wl_proxy_marshal_constructor_versioned>
(gdb) print WAYLAND_wl_proxy_marshal_constructor_versioned
$2 = (struct wl_proxy *(*)(struct wl_proxy *, uint32_t, 
    const struct wl_interface *, uint32_t, ...)) 0x0
(gdb)


### Pretty sure I am running Wayland:
### - Picked it at the login screen
### - "lg" shows some Wayland windows active
### - "ps" shows Wayland process no Xorg processes

[jman@talos test_sdl]$ ps fwww
  PID TTY      STAT   TIME COMMAND
25208 tty2     Ssl+   0:00 /usr/libexec/gdm-wayland-session gnome-session
25210 tty2     Sl+    0:00  \_ /usr/libexec/gnome-session-binary
25230 tty2     Sl+    7:13      \_ /usr/bin/gnome-shell
25246 tty2     Sl+    2:23      |   \_ /usr/bin/Xwayland :0 -rootless -noreset -listen 4 -listen 5 -displayfd 6
25536 tty2     Rl+   31:08      |   \_ /usr/lib64/firefox/firefox
25900 tty2     Sl+    0:02      |   \_ /usr/bin/python /usr/bin/terminator
25908 tty2     S+     0:00      |   |   \_ gnome-pty-helper
25909 pts/0    Ss     0:00      |   |   \_ /bin/bash
13879 pts/0    R+     0:00      |   |       \_ ps fwww
27670 tty2     Sl+    0:28      |   \_ gedit
28820 tty2     Sl+    0:49      |   \_ /usr/bin/python /usr/bin/terminator
28827 tty2     S+     0:00      |   |   \_ gnome-pty-helper
28828 pts/1    Ss     0:01      |   |   \_ /bin/bash
13847 pts/1    Sl+    0:00      |   |   |   \_ gdb ./test_sdl
 3104 pts/2    Ss+    0:00      |   |   \_ /bin/bash
 9094 tty2     Sl+    0:00      |   \_ /usr/bin/python /usr/bin/terminator
 9101 tty2     S+     0:00      |       \_ gnome-pty-helper
 9102 pts/3    Ss+    0:00      |       \_ /bin/bash
25279 tty2     Sl+    0:12      \_ /usr/libexec/gnome-settings-daemon
25359 tty2     SNl+   0:00      \_ /usr/libexec/tracker-miner-apps
25365 tty2     Sl+    0:00      \_ /usr/bin/python /usr/libexec/gnome-tweak-tool-lid-inhibitor
25367 tty2     Sl+    0:01      \_ /usr/bin/gnome-software --gapplication-service
25368 tty2     SNl+   0:00      \_ /usr/libexec/tracker-extract
25369 tty2     SNl+   0:00      \_ /usr/libexec/tracker-miner-user-guides
25370 tty2     Sl+    0:00      \_ abrt-applet
25384 tty2     S+     0:00      \_ /usr/bin/seapplet
25397 tty2     SNl+   0:00      \_ /usr/libexec/tracker-miner-fs
25402 tty2     Sl+    0:00      \_ /usr/libexec/evolution/evolution-alarm-notify
25377 tty2     Sl+    0:00 /usr/libexec/gsd-printer


[jman@talos test_sdl]$ lshw -short | grep display
/0/100/2                   display        HD Graphics 5300