XLookupString return inconsistent

[martin f krafft]

Hello,

My window manager uses the number keys to switch between tags (it's
"awesome"). I noticed that for a while, I was no longer able to move
a client to tag "2" (Mod4-Shift-2), while moving to other tags
worked fine. Also, I could still switch to tag "2" (Mod4-2), so it
was something about the shift key, I gathered.

Well, not so. Using xev, I discovered the following:

Entering "1" and "2" into the xev gives consistent results. Holding
down shift yields "!" and "@" as it should for a US keyboard.

However, as soon as I touch Control_L or Control_R at the same time,
something weird happens. Here's the output for Control_L + 1:

  KeyPress event, serial 1684, synthetic NO, window 0x4200001,
      root 0x4b9, subw 0x0, time 4065591518, (117,69), root:(3486,798),
      state 0x14, keycode 10 (keysym 0x31, 1), same_screen YES,
      XLookupString gives 1 bytes: (31) "1"
      XmbLookupString gives 1 bytes: (31) "1"
      XFilterEvent returns: False

but look at what happens for Control_L + 2:

  KeyPress event, serial 1684, synthetic NO, window 0x4200001,
      root 0x4b9, subw 0x0, time 4065592038, (117,69), root:(3486,798),
      state 0x14, keycode 11 (keysym 0x32, 2), same_screen YES,
      XLookupString gives 1 bytes: (00) ""
      XmbLookupString gives 1 bytes: (00) ""
      XFilterEvent returns: False

Note how the keysym is correct, but then XLookupString and/or
XmbLookupString instead return the empty string.

This happens whether I load the US or the DE xkb map, using
setxkbmap.

Do you have any idea what might be going on?

-- 
@martinkrafft | http://madduck.net/ | http://two.sentenc.es/
 
"she was rather too intelligent and competent-looking to be
 considered entirely beautiful, but all the more attractive because
 of it."
                           -- george spencer-brown, "a lion's teeth"
 
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