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Date: Wed, 27 Oct 2010 17:28:00 -0000
From: Jan Kratochvil <jan.kratochvil@redhat.com>
To: Eran Ifrah <eran.ifrah@gmail.com>
Cc: gdb@sourceware.org
Subject: Re: GDB/MI - var-update/create BUG
Message-ID: <20101027170327.GA11455@host1.dyn.jankratochvil.net>
References: <AANLkTinUo3LMBBmDWPm_jp2md3Xzi=06NBf2qJ2S6NF2@mail.gmail.com>
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On Tue, 26 Oct 2010 18:01:30 -0400, Eran Ifrah wrote:
> If I have a local variable with the same name in different scopes,
> when switching between the scopes the content of the variable object
> does not reflect the new variable.

This is correct from the GDB's point of view, normally you want to track that
_variable_, not that _name_. Anywhere you are.

You should use '@' instead of '*' for frame if you want to track it by name,
see "floating" in: info '(gdb)GDB/MI Variable Objects'


Thanks,
Jan


g++ -o 2 2.C -Wall -g
gdb -nx -i=mi <2.cmd ./2

==> 2.C <==
#include <string>
void foo() {
        std::string mystr = " second value ";
        mystr += " appended content";
}
int main(int argc, char **argv) {
       	std::string mystr = " first value ";
       	foo();
        mystr += " appended content";
        return 0;
}

==> 2.cmd <==
-break-insert -t 8
-exec-run
-var-create - * mystr._M_dataplus._M_p
-break-insert -t 4
-exec-continue
-var-update *
-var-evaluate-expression "var1"

->
^done,value="0x601028 \" first value \""

==> 2-floating.cmd <==
-break-insert -t 8
-exec-run
-var-create - @ mystr._M_dataplus._M_p
-break-insert -t 4
-exec-continue
-var-update *
-var-evaluate-expression "var1"

->
^done,value="0x601058 \" second value \""