Re: Problem with NSTextView

[Sebastian Reitenbach]

On Saturday, January 28, 2012 14:44 CET, David Chisnall <theraven@sucs.org> 
wrote: 
 
> Hi Sebastian,
> 
> If you put a breakpoint on objc_selector_type_mismatch, you will enter the 
> debugger whenever this is warning will be printed.

OK, so I did (actually it did not picked it up, so I set a breakpoint on 
fprintf)

I found in -gui, NSText, NSImageView, and NSMovieView, the copy: and paste: 
methods return values are void.

but in NSPasteboard.m, the example there for paste: suggests to return id, it 
does a return self; at the end.

I haven't found a method copy: paste: method declared with id as return value. 
But my guess now is that 
this comes from Gorm.


I also wonder, why the hell it checks this that often. For example, in 
Addresses, I edit a field, and then hover with the mouse
over the application window. While doing so, I can see, the console gets 
spammed with the mentioned warning.
So I wonder why its checking for copy: and paste: at all just because I move my 
mouse over the application.

#0  fprintf (fp=0x2d086310, fmt=0x2ccc6c6f "Calling [%s %c%s] with incorrect 
signature.  Method has %s, selector has %s\n")
    at /usr/src/lib/libc/stdio/fprintf.c:44
#1  0x0ccdb448 in objc_selector_type_mismatch (cls=0xcfbd5274, 
selector=0xcfbd5274, result=0xcfbd5274) at sendmsg2.c:37
#2  0x0ccdc22c in objc_get_slot (cls=Unhandled dwarf expression opcode 0x0
) at sendmsg2.c:307
#3  0x0ccdc26f in class_respondsToSelector (cls=dwarf2_read_address: Corrupted 
DWARF expression.
) at sendmsg2.c:322
#4  0x0a102e78 in -[NSObject respondsToSelector:] (self=dwarf2_read_address: 
Corrupted DWARF expression.
) at NSObject.m:2096
#5  0x09977ff1 in -[NSApplication(Private) 
_targetForAction:keyWindow:mainWindow:] (self=0x8a57a984, _cmd=0x29805088, 
    aSelector=0x8be49550, keyWindow=0x7fbfe304, mainWindow=0x7fbfe304) at 
NSApplication.m:3897
#6  0x0996dae1 in -[NSApplication targetForAction:] (self=0x8a57a984, 
_cmd=0x29804d08, aSelector=0x8be49550)
    at NSApplication.m:2290
#7  0x0996d98c in -[NSApplication targetForAction:to:from:] (self=0x8a57a984, 
_cmd=0x29837640, theAction=0x8be49550, 
    theTarget=0x0, sender=0x84fdf904) at NSApplication.m:2275
#8  0x09b2891c in -[NSMenu update] (self=0x80ffd844, _cmd=0x29837190) at 
NSMenu.m:1151
#9  0x09b287f2 in -[NSMenu update] (self=0x81921144, _cmd=0x29805228) at 
NSMenu.m:1146
#10 0x09969901 in -[NSApplication run] (self=0x8a57a984, _cmd=0x297fe900) at 
NSApplication.m:1570
#11 0x0992466d in NSApplicationMain (argc=1, argv=0xcfbd5c14) at Functions.m:91
#12 0x1c005ec7 in ___start ()
#13 0x1c005e42 in _start ()


Sebastian

> 
> On 28 Jan 2012, at 13:17, Sebastian Reitenbach wrote:
> 
> > Method has v12@0:4@8, selector has @12@0:4@8
> 
> This looks potentially dangerous.  The caller is expecting the method to 
> return an object, but the method is a standard IBAction (i.e. returning 
> void).  If the caller does anything with the return value, then it will 
> likely crash...
> 
> David
> 
> 
> 
> -- Sent from my Difference Engine
> 
> 
>