Re: scope in nested function

[Ramana Radhakrishnan <ramana.radhakrishnan@codito.com>]

Is this something gdb was never designed to do ? A quick search in the
doco didn't reveal anything for me . The only reference is that of
Pascal programs not supporting debug for nested functions. 

ramana@arnor:~$ arm-none-eabi-gcc -v
Using built-in specs.
Target: arm-none-eabi
Configured
with: /mnt/tools/fsf/build/combined-arm-none-eabi-svn-4-1-branch-2006-03-30/configure --target=arm-none-eabi --prefix=/mnt/tools/fsf/install/arm-none-eabi-svn-4-1-branch-2006-03-30 --enable-languages=c --disable-nls --with-newlib --disable-gdbtk --disable-libssp
Thread model: single
gcc version 4.1.1 20060330 (prerelease)


ramana@arnor:~$ arm-none-eabi-gcc -g nestedfns.c
ramana@arnor:~$ arm-none-eabi-gdb a.out
GNU gdb 6.4.50.20060103-cvs
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you
are
welcome to change it and/or distribute copies of it under certain
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for
details.
This GDB was configured as "--host=i686-pc-linux-gnu
--target=arm-none-eabi".../home/ramana/.gdbinit:1: Error in sourced
command file:
Junk in argument list: " brkoninsnraw"

(gdb) b main::foo
Can't find member of namespace, class, struct, or union named
"main::foo"
Hint: try 'main::foo<TAB> or 'main::foo<ESC-?>
(Note leading single quote.)
(gdb) b foo
Function "foo" not defined.
Make breakpoint pending on future shared library load? (y or [n]) n
(gdb) b foo.1958
Can't find member of namespace, class, struct, or union named "foo.1958"
Hint: try 'foo.1958<TAB> or 'foo.1958<ESC-?>
(Note leading single quote.)
(gdb)


Is gdb even designed to do this. ? A google reveals this thread where a
user has mentioned problems with nested functions . The mechanism though
which is used is only using line numbers .... so .... we don't really
know if it was ever designed to work ! 

http://sourceware.org/ml/gdb/2005-02/msg00141.html

cheers
Ramana


On Fri, 2006-03-31 at 06:57 +0100, Bill Pursell wrote:
> I'm not sure how to reference a variable in a nested function from gdb.
> In the gdb session below, there are 2 things I don't understand
> how to do:
> 
> 1) how do I set a breakpoint in foo? (other than by referencing a line
>       	number)
> 2) when I'm in foo, how do I reference i?
> 
> 
> #include <stdio.h>
> 
> int
> main()
> {
>       auto void foo(void);
>       int i = 0;
>       foo();
>       return 0;
> 
>       void foo(void) {
>           i += 1;
>       }
> }
> 
> 
> 
> 
> (gdb) b main
> Breakpoint 1 at 0x8048361: file d.c, line 7.
> (gdb) run
> Starting program: /home/bill/tmp/a.out
> 
> Breakpoint 1, main () at d.c:7
> 7           int i = 0;
> (gdb) b foo
> Function "foo" not defined.
> Make breakpoint pending on future shared library load? (y or [n]) n
> (gdb) n
> 8           foo();
> (gdb) s
> foo.0 () at d.c:11
> 11          void foo(void) {
> (gdb) p i
> No symbol "i" in current context.
> (gdb) n
> 12              i += 1;
> (gdb) cont
> Continuing.
> 
> Program exited normally.
-- 
Ramana Radhakrishnan
GNU Tools
codito ergo sum (http://www.codito.com)