[PATCH] Introduce "gdb/configure.nat" (and delete "gdb/config/*/*.mh" files)

[Simon Marchi]

On 2017-05-02 15:28, Sergio Durigan Junior wrote:
>>> +# Variables defined here:
>>> +#
>>> +# NAT_FILE
>>> +# NATDEPFILES
>>> +# NAT_CDEPS
>>> +# LOADLIBES
>>> +# MH_CFLAGS
>>> +# XM_CLIBS
>>> +# NAT_GENERATED_FILES
>>> +# HAVE_NATIVE_GCORE_HOST
>>> +# NAT_EXTRA_FRAGS_FILE
>> 
>> Could you document (if you know it) what each variable does?
> 
> Sure.  Here's what I know what them.  What do you think?
> 
> # Variables defined here:
> #
> # NAT_FILE - The header file with definitions for this host

Looks good.

> #
> # NATDEPFILES - The depfiles to be compiled for this host

"depfiles" is not so clear I think.  Perhaps

   NATDEPFILES - Source files required for native debugging on this host.

> #
> # NAT_CDEPS - Dynamic symbols to be exported for libthread_db

Looks good.

> #
> # LOADLIBES - Libraries that will be linked against GDB for this host

Don't we usually say the reverse, the program is linked against the 
libraries?

   LOADLIBES - Libraries against which GDB will be linked for this host.

> #
> # MH_CFLAGS - Additional CFLAGS for this host

Looks good.

> #
> # XM_CLIBS - Host-dependent libs to be linked against GDB.

Same comment about "linked against".

> # NAT_GENERATED_FILES - Generated files by this host

by -> for?

   NAT_GENERATED_FILES - Generated files for this host.

> # HAVE_NATIVE_GCORE_HOST -

I just noticed that this variable is not defined in Makefile.in.  
configure.ac AC_SUBST's _TARGET twice, but not _HOST, so I think you 
confused them.

But to be honest, I am also completely confused by what those two 
variables do.

> # NAT_EXTRA_FRAGS_FILE - Extra Makefile fragmentsFile containing extra 
> fragments of Makefile
> #                        that will be used by this host.

That could be shortened to

   NAT_EXTRA_FRAGS_FILE - Extra Makefile fragments that will be used for 
this host.

Make sure they all end (or don't end) with a period, for consistency.

Perhaps someone could shed some light on the obscure variables names?  
What do the XM_ and MH_ prefixes stand for?  What's the difference 
between XM_CLIBS and LOADLIBES (and why is it called "LIBES"?) ?

>> IMO, the interest of having all of this in a single file is to be able
>> to factor out common things.  A lot of NATDEPFILES are repeated Would
>> it be possible to have a switch on ${gdb_host} at the top level, and
>> specify all the files specific to OSes but machine-agnostic?  For
>> example, fork-child.o and inf-ptrace.o probably appear in all the
>> linux ports.
> 
> Fair point.  I will address what you and Jon mentioned, and resubmit 
> the
> patch with the modifications.

Ok.  But as John mentioned, it's probably better if this patch is a 
simple translation of what's already there, and any "optimization" 
coming in a subsequent patch.  It will be easier to track the changes.

Thanks,

Simon