Platform tested: openSUSE Leap 15.1
Version: SDL 2.0.12, which was built with --enable-ime.
Other components: ibus-1.5.19, dbus-1.12.2

Testcase:
#include <SDL2/SDL.h>
int main()
{
        SDL_InitSubSystem(SDL_INIT_VIDEO);
        SDL_Window *w = SDL_CreateWindow("", 0, 0, 640, 480, 0);
        bool trigger_crash = true;
        if (trigger_crash) {
                SDL_Event ev;
                do {
                } while (SDL_PollEvent(&ev) <= 0);
        }
        SDL_CreateRenderer(w, 0, SDL_WINDOW_OPENGL);
}


Crash/SIGSEGV.

(gdb) bt
#0  X11_GetWindowWMInfo (_this=0x61a130, window=0x7f4d70, info=0x7fffffffd220)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/video/x11/SDL_x11window.c:1665
#1  0x00007ffff7b6a709 in SDL_IBus_UpdateTextRect (rect=rect@entry=0x0)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/core/linux/SDL_ibus.c:538
#2  0x00007ffff7b6ae80 in IBus_MessageHandler (conn=<optimized out>, 
    msg=msg@entry=0x6684a0, user_data=user_data@entry=0x7ffff7dd3a60 <dbus>)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/core/linux/SDL_ibus.c:160
#3  0x00007ffff4874740 in _dbus_object_tree_dispatch_and_unlock (
    tree=0x666c50, message=message@entry=0x6684a0, 
    found_object=found_object@entry=0x7fffffffd458) at dbus-object-tree.c:1020
#4  0x00007ffff486552a in dbus_connection_dispatch (connection=0x666a10)
    at dbus-connection.c:4744
#5  0x00007ffff7b6b095 in SDL_IBus_PumpEvents ()
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/core/linux/SDL_ibus.c:576
#6  0x00007ffff7b52bc5 in X11_PumpEvents (_this=_this@entry=0x61a130)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/video/x11/SDL_x11events.c:1468
#7  0x00007ffff7b58b67 in X11_GL_InitExtensions (_this=0x61a130)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/video/x11/SDL_x11opengl.c:470
#8  X11_GL_LoadLibrary (_this=0x61a130, path=<optimized out>)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/video/x11/SDL_x11opengl.c:235
#9  0x00007ffff7b2a526 in SDL_GL_LoadLibrary_REAL (path=path@entry=0x0)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/video/SDL_video.c:2915
#10 0x00007ffff7b2a854 in SDL_RecreateWindow (window=window@entry=0x7f4d70, 
    flags=flags@entry=518)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/video/SDL_video.c:1680
#11 0x00007ffff7ac55c9 in GL_CreateRenderer (window=0x7f4d70, flags=2)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/render/opengl/SDL_render_gl.c:1592
#12 0x00007ffff7abff70 in SDL_CreateRenderer_REAL (window=0x7f4d70, index=0, 
    flags=2)
    at /usr/src/debug/SDL2-2.0.12-lp151.111.1.x86_64/src/render/SDL_render.c:837
#13 0x0000000000400709 in main () at x.cpp:12

frame 0.
1661    SDL_bool
1662    X11_GetWindowWMInfo(_THIS, SDL_Window * window, SDL_SysWMinfo * info)
1663    {
1664        SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
1665>       Display *display = data->videodata->display;

driverdata is NULL because the window was already destroyed near the start of SDL_RecreateWindow.

Can you reproduce? If not, I'll write up a more detailed report.