(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
weston_surface_from_global_float (surface=0xffffffffffffff80, x=542, y=114,
    sx=0x7ffffaad8b88, sy=0x7ffffaad8b8c) at compositor.c:763
763             if (surface->transform.enabled) {
(gdb) bt full
#0  weston_surface_from_global_float (surface=0xffffffffffffff80, x=542, y=114,
    sx=0x7ffffaad8b88, sy=0x7ffffaad8b8c) at compositor.c:763
No locals.
#1  0x000000000040a77d in weston_surface_from_global_fixed (
    surface=surface@entry=0xffffffffffffff80, x=x@entry=138752, y=138752,
    y@entry=29184, sx=sx@entry=0x7ffffaad8bf8, sy=sy@entry=0x7ffffaad8bfc)
    at compositor.c:792
        sxf = 1.94432965e-40
        syf = 114
#2  0x000000000040ad8c in weston_compositor_pick_surface (compositor=0x18d4dc0,
    x=138752, y=29184, sx=sx@entry=0x7ffffaad8bf8, sy=sy@entry=0x7ffffaad8bfc)
    at compositor.c:948
        surface = 0xffffffffffffff80
#3  0x00007f319519ab5d in popup_grab_focus (grab=<optimized out>) at shell.c:2023
        pointer = 0x1994fc0
        surface = <optimized out>
        shseat = <optimized out>
        client = 0x1a6eab0
        sx = <optimized out>
        sy = 29184
#4  0x00007f319519f101 in add_popup_grab (shseat=0x1a05690, shsurf=0x1b28ed0)
    at shell.c:2124
        seat = 0x1972340
#5  shell_map_popup (shsurf=0x1b28ed0) at shell.c:2156
        shseat = 0x1a05690
        es = <optimized out>
        parent = <optimized out>
#6  map (sy=27285184, sx=<optimized out>, height=149, width=<optimized out>,
    surface=0x1b2ae60, shell=0x1963fb0) at shell.c:3403
        surface_type = SHELL_SURFACE_POPUP
        parent = <optimized out>
        ws = <optimized out>
        panel_height = 0
        surf_y = <optimized out>
        compositor = 0x18d4dc0
        shsurf = 0x1b28ed0
        seat = <optimized out>
        surf_x = <optimized out>
#7  shell_surface_configure (es=0x1b2ae60, sx=<optimized out>, sy=27285184,
    width=<optimized out>, height=149) at shell.c:3536
        shsurf = 0x1b28ed0
        shell = 0x1963fb0
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