NSConnection-spawned runloop conflicting with "real" runloop?

[Ondřej Hošek]

Dear GNUstep developers and users,

I am having trouble with all GUI-based GNUstep applications on my
machine. (I have trunk of clang, libobjc2, base, gui, back and
gworkspace installed.) Anytime I try to start a GUI program (including
GWorkspace), it becomes stuck in a runloop caused by NSConnection
before it has a chance to enter the "real" runloop.

The backtrace follows:

#0  0x00007ffff5c15683 in poll () from /lib/libc.so.6
#1  0x00007ffff677c92e in -[GSRunLoopCtxt pollUntil:within:] (
    self=<value optimized out>, _cmd=<value optimized out>,
    milliseconds=<value optimized out>, contexts=<value optimized out>)
    at GSRunLoopCtxt.m:424
#2  0x00007ffff66d3fc4 in -[NSRunLoop acceptInputForMode:beforeDate:] (
    self=<value optimized out>, _cmd=<value optimized out>,
    mode=<value optimized out>, limit_date=<value optimized out>)
    at NSRunLoop.m:1198
#3  0x00007ffff66d4328 in -[NSRunLoop runMode:beforeDate:] (
    self=<value optimized out>, _cmd=Unhandled dwarf expression opcode 0x0
) at NSRunLoop.m:1266
#4  0x00007ffff6634d9d in -[NSConnection(Private) _getReplyRmc:] (
    self=0x116f6b0, _cmd=0x7ffff6b02b30, sn=0) at NSConnection.m:3186
#5  0x00007ffff66291ef in -[NSConnection rootProxy] (self=0x116f6b0,
    _cmd=0x710cf0) at NSConnection.m:1671
#6  0x00007ffff6622207 in +[NSConnection
rootProxyForConnectionWithRegisteredName:host:usingNameServer:]
(self=0x7ffff6b02a50, _cmd=0x7ffff6b0f300,
    n=0x7ffff6b0fbd0, h=0x7ffff6b0fbb0, s=0x112f950) at NSConnection.m:746
#7  0x00007ffff665e5a5 in -[NSDistributedNotificationCenter(Private) _connect]
    (self=<value optimized out>, _cmd=Unhandled dwarf expression opcode 0x0
)
    at NSDistributedNotificationCenter.m:682
#8  0x00007ffff665d7e0 in -[NSDistributedNotificationCenter
addObserver:selector:name:object:suspensionBehavior:] (self=<value
optimized out>,
    _cmd=<value optimized out>, anObserver=<value optimized out>,
    aSelector=<value optimized out>, notificationName=<value optimized out>,
    anObject=<value optimized out>, suspensionBehavior=Unhandled dwarf
expression opcode 0x0
)
    at NSDistributedNotificationCenter.m:338
#9  0x00007ffff665d51e in -[NSDistributedNotificationCenter
addObserver:selector:name:object:] (self=<value optimized out>,
_cmd=0x4,
    anObserver=<value optimized out>, aSelector=<value optimized out>,
    notificationName=<value optimized out>, anObject=<value optimized out>)
    at NSDistributedNotificationCenter.m:263
#10 0x00007ffff711b0e9 in -[_GSWorkspaceCenter init] (
    self=<value optimized out>, _cmd=Unhandled dwarf expression opcode 0x0
) at NSWorkspace.m:292
#11 0x00007ffff711c78f in -[NSWorkspace init] (self=Unhandled dwarf
expression opcode 0x0
) at NSWorkspace.m:692
#12 0x00007ffff711c5b5 in +[NSWorkspace sharedWorkspace] (
    self=<value optimized out>, _cmd=Unhandled dwarf expression opcode 0x0
) at NSWorkspace.m:644
#13 0x00007ffff701e960 in -[NSDocumentController init] (
    self=<value optimized out>, _cmd=<value optimized out>)
    at NSDocumentController.m:312
#14 0x00007ffff701e621 in +[NSDocumentController sharedDocumentController] (
    self=Unhandled dwarf expression opcode 0x0
) at NSDocumentController.m:257
#15 0x00007ffff6fc423b in -[NSApplication(Private)
_targetForAction:keyWindow:mainWindow:] (self=<value optimized out>,
_cmd=<value optimized out>,
    aSelector=<value optimized out>, keyWindow=<value optimized out>,
    mainWindow=<value optimized out>) at NSApplication.m:3929
#16 0x00007ffff6fc03e8 in -[NSApplication targetForAction:to:from:] (
    self=<value optimized out>, _cmd=Unhandled dwarf expression opcode 0x0
) at NSApplication.m:2295
#17 0x00007ffff7066a40 in -[NSMenu update] (self=<value optimized out>,
    _cmd=<value optimized out>) at NSMenu.m:1157
#18 0x00007ffff7066921 in -[NSMenu update] (self=<value optimized out>,
    _cmd=<value optimized out>) at NSMenu.m:1144
#19 0x00007ffff7065f36 in -[NSMenu itemChanged:] (self=Unhandled dwarf
expression opcode 0x0
) at NSMenu.m:850
#20 0x00007ffff70712fa in -[NSMenuItem setTarget:] (
    self=<value optimized out>, _cmd=Unhandled dwarf expression opcode 0x0
) at NSMenuItem.m:463
#21 0x00007ffff7070663 in -[NSMenuItem setSubmenu:] (
    self=<value optimized out>, _cmd=Unhandled dwarf expression opcode 0xcf
) at NSMenuItem.m:236
#22 0x0000000000452cc1 in -[GWorkspace createMenu] (self=0x117d920, _cmd=0x4)
    at GWorkspace.m:186
#23 0x0000000000453bc4 in -[GWorkspace applicationWillFinishLaunching:] (
    self=<value optimized out>, _cmd=<value optimized out>,
    aNotification=<value optimized out>) at GWorkspace.m:333
#24 0x00007ffff669433b in -[NSNotificationCenter _postAndRelease:] (
    self=<value optimized out>, _cmd=<value optimized out>,
    notification=<value optimized out>) at NSNotificationCenter.m:1161
#25 0x00007ffff6fbce39 in -[NSApplication finishLaunching] (
    self=<value optimized out>, _cmd=<value optimized out>)
    at NSApplication.m:1028
#26 0x00007ffff6fbe9cd in -[NSApplication run] (self=<value optimized out>,
    _cmd=Unhandled dwarf expression opcode 0xee
) at NSApplication.m:1560
#27 0x0000000000450eb6 in main (argc=18340128, argv=0x4, env=0x493df)
    at main.m:38

(Pay no mind to the purported variable content; clang is not very
successful at generating useful debug information yet.)

Can somebody please shed some light on this? I'm not versed in
GNUstep's implementation details, and I'm out of ideas which part of
the chain to probe next.

Thanks a lot!

Cheers,
~~ Ondra