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From: Nick Roberts <nickrob@snap.net.nz>
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Date: Thu, 22 Mar 2007 10:32:00 -0000
To: Vladimir Prus <ghost@cs.msu.su>
Cc: gdb@sources.redhat.com
Subject: Re: Behaviour of invalid varobjs
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 > I think current mainline does something strange
 > about varobjs that cannot be evaluated:
 > 
 >         -var-create null_ptr * **0
 >         ^done,name="null_ptr",numchild="0",value="0",type="int"
 >         (gdb)
 >         -var-update null_ptr
 >         ^done,changelist=[{name="null_ptr",in_scope="false"}]
 > 
 > First, the value of "**0" is not 0, in fact there's no value at all.
 > Second, given that nothing was changed between the two commands,
 > it's strange that 'null_ptr' is mentioned in -var-update.
 > 
 > Before I go changing code, do everybody agree that:
 > 
 > 1. The output of -var-create should either have no "value"
 > field at all, or value="", as is used in some other context.
 > 2. The output of -var-update should not include anything.
 > 
 > Also, we probably should include in_scope="false" in output of

            probably should not include?

 > -var-create, but I'm not quite sure.

Are there any real situations where you would want to create a variable object
of a constant?  If not, then, apart from ensuring that such objects don't crash
GDB, I don't think this is an urgent issue.

-- 
Nick                                           http://www.inet.net.nz/~nickrob