Re: Displaying structure members named like C keywords.

[Sergio Durigan Junior]

On Friday, August 22 2014, Emilio Lopes wrote:

>> Would it be possible for you to come up with a simpler reproducer
>> and send it to this list?  I am guessing there is something else in
>> your code that might be triggering this.
>
> I was hoping for this to be something simple...  Oh, well.

Yeah, sometimes issues are not so simple...

> As you can imagine this is a somewhat larger codebase, with lots of
> automatically generated code from XML files, using those structures.

Sure, that is also why I asked for a simpler reproducer :-).

>     (gdb) p P_SLAVE_CMDS_OPTIONS_HAL_OPTMIN_ENABLED
>     $1 = (struct param_t *) 0x10db9c <_slave_cmds_options_hal_optmin>
>     (gdb) set sysroot ~/projects/hal/system/platform-tam3517/root-debug
>     Reading symbols from
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libpthread.so.0...done.
>     Loaded symbols for
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libpthread.so.0
>     Reading symbols from
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/librt.so.1...done.
>     Loaded symbols for
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/librt.so.1
>     Reading symbols from
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libstdc++.so.6...done.
>     Loaded symbols for
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libstdc++.so.6
>     Reading symbols from
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libm.so.6...done.
>     Loaded symbols for
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libm.so.6
>     Reading symbols from
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libgcc_s.so.1...done.
>     Loaded symbols for
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libgcc_s.so.1
>     Reading symbols from
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libc.so.6...done.
>     Loaded symbols for
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/libc.so.6
>     Reading symbols from
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/ld-linux.so.3...done.
>     Loaded symbols for
> /home/lopes/projects/hal/system/platform-tam3517/root-debug/lib/ld-linux.so.3
>     (gdb) p P_SLAVE_CMDS_OPTIONS_HAL_OPTMIN_ENABLED
>     A syntax error in expression, near
> `complex.paramv[29].info.complex.paramv[0].info.complex.paramv[1].info.complex.paramv[0])'.
>     (gdb) set sysroot ''
>     warning: Unable to find dynamic linker breakpoint function.
>     GDB will be unable to debug shared library initializers
>     and track explicitly loaded dynamic code.
>     (gdb) p P_SLAVE_CMDS_OPTIONS_HAL_OPTMIN_ENABLED
>     $2 = (struct param_t *) 0x10db9c <_slave_cmds_options_hal_optmin>
>     (gdb)
>
> Problems come and go as I set/unset `sysroot'!!! (I'm debugging code
> running on an ARM evaluation board remotely.)

Hm, OK, I'm thinking about some issue with symbols here (visibility
maybe).  I made lots of attempts here to reproduce it based on what you
posted, but I still cannot see this behavior using GDB from git HEAD.

If you cannot give more instructions on how to reproduce this, then I
have to ask you to file a bug against GDB on
<https://sourceware.org/bugzilla>, please.

> Can you give me a hint on what to look for from here?

There are a few debug triggers that you can enable on GDB.  Maybe 'set
debug expression 1' could help.  Also, you can use 'maintenance print
symbols <filename>' to print all the symbols; this could help analyzing
if 'complex' is being hidden by some other library.  Feel free to post
those things here.

Cheers,

-- 
Sergio
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