Re: [PATCH v4 2/2] gdb: CTF support

[Tom Tromey <tom@tromey.com>]

>>>>> Wei-min Pan <weimin.pan@oracle.com> writes:

>> I didn't look, did the top-level changes go in to gcc?
>> The top-level configury code is canonically maintained there.

> Given the following rules in Makefile.def:

> dependencies = { module=configure-gcc; on=all-binutils; };
> dependencies = { module=all-binutils; on=all-libctf; };
> dependencies = { module=all-gdb; on=all-libctf; };

> binutils gets built before gcc does. It's not clear why making changes
> into gcc is needed?

Sorry, I was not clear enough.

Most top-level files, like Makefile.def, are shared between gcc and
gdb+binutils.  However, gcc and gdb have different source repositories.
In order to reduce the possibility of long-term divergence, the gcc
repository was declared the canonical repository -- in general (there
are exceptions) -- changes are checked in first there, then brought over
to the gdb repository.

My question was whether you did this.

>> It's preferable to use the type-safe registry approach in new code.

> This register key was not intended to manage the object with new/delete
> but to be used to close file descriptors that are associated with the
> ctf file/archive.

It's still preferable to use the type-safe approach.  You can easily
introduce a new deleter object that works just as you like.  In fact the
code will nearly be identical -- just type-safe.

>> gdb doesn't generally use typedefs like this, especially now that it's
>> in C++.

> It seems there are several places, e.g. aarch64-tdep.c, event-loop.c,
> linespec.c, procfs.c, that do. We can drop "typedef" if you prefer.

Yes, I'm afraid you can't always judge the current standard in gdb by
the existing code, because the transition from C to C++ did not also
involve updating every single thing -- just the important things.

>> Instead of this function, it's more usual in gdb to use:
>> 
>>        CORE_ADDR baseaddr
>>        = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile));
>> 
>> Maybe this function is even wrong in some situation, I'm not sure.

> You suspect that bfd_get_section_by_name might return a wrong *asection?
> Yes, we can use ANOFFSET, as you suggested, for the text base but still
> need to get the size of the text section.

I'm not sure if it can or not.  Anyway it seems you can use
SECT_OFF_TEXT to also get the size... ?

thanks,
Tom