Re: Making mi -add-inferior command consistent with ci

[Andrew Burgess <aburgess@redhat.com>]

Muhammad Umair Sair via Gdb-patches <gdb-patches@sourceware.org> writes:

> From 3729f798d1f75a74eefe0c240d8c4c9849dac308 Mon Sep 17 00:00:00 2001
> From: Umair Sair <umair_sair@hotmail.com>
> Date: Tue, 22 Feb 2022 01:40:06 +0500
> Subject: [PATCH] Making mi -add-inferior command consistent with ci
>
> With multi-target debugging support in gdb, add-inferior command without
> arguments in console interpreter adds a new inferior and sets the connection
> of previously selected inferior as the connection of new inferior as well.
> But the same command for machine interpreter is not setting the connection
> for new inferior. This commit fixes this issue and makes the console and
> machine interpreter behavior consistent for add-inferior command.

We're usually pretty conservative about changing MI behaviour in non
backward compatible ways.  I'm not entirely sure that this change wont
cause problems for an existing f/e that is using -add-inferior?

Maybe I'm worrying about nothing?  I'm open to being convinced.

Another option would be to add a new option, e.g.:

  -add-inferior [--connection NUM]

or

  -add-inferior [--inherit-connection]


> ---
>  gdb/ChangeLog    | 9 +++++++++
>  gdb/inferior.c   | 4 ++--
>  gdb/inferior.h   | 5 ++++-
>  gdb/mi/mi-main.c | 4 +++-
>  4 files changed, 18 insertions(+), 4 deletions(-)
>
> diff --git a/gdb/ChangeLog b/gdb/ChangeLog
> index dfee3dad157..1f342cc628f 100644
> --- a/gdb/ChangeLog
> +++ b/gdb/ChangeLog
> @@ -1,3 +1,12 @@
> +2022-02-22  Umair Sair  <umair_sair@hotmail.com>
> +
> +	* gdb/inferior.c (switch_to_inferior_and_push_target): allowing
> +	access to this function outside of file.
> +	* gdb/inferior.h (switch_to_inferior_and_push_target): added extern
> +	entry for function in header.
> +	* gdb/mi/mi-main.c (mi_cmd_add_inferior): new inferior should use
> +	the connection from previously selected inferior.
> +

We no longer maintain ChangeLog in gdb, so this part is not needed.
You're welcome to keep the ChangeLog text in the commit message in
_addition_ to the long form description, but this is not a requirement.

>  2021-04-23  Tom Tromey  <tromey@adacore.com>
>  
>  	PR gdb/27743:
> diff --git a/gdb/inferior.c b/gdb/inferior.c
> index 4fdddbcb55b..16e4279bc1a 100644
> --- a/gdb/inferior.c
> +++ b/gdb/inferior.c
> @@ -1,6 +1,6 @@
>  /* Multi-process control for GDB, the GNU debugger.
>  
> -   Copyright (C) 2008-2021 Free Software Foundation, Inc.
> +   Copyright (C) 2008-2022 Free Software Foundation, Inc.
>  

Not sure what's going on here.  The patch shows all the dates changing,
but all the files you've changed already have 2022 in the upstream
master branch.

Thanks,
Andrew

>     This file is part of GDB.
>  
> @@ -740,7 +740,7 @@ add_inferior_with_spaces (void)
>     NO_CONNECTION is true, push the process_stratum_target of ORG_INF
>     to NEW_INF.  */
>  
> -static void
> +void
>  switch_to_inferior_and_push_target (inferior *new_inf,
>  				    bool no_connection, inferior *org_inf)
>  {
> diff --git a/gdb/inferior.h b/gdb/inferior.h
> index fb7d0c2bc1a..d4abd00489a 100644
> --- a/gdb/inferior.h
> +++ b/gdb/inferior.h
> @@ -1,7 +1,7 @@
>  /* Variables that describe the inferior process running under GDB:
>     Where it is, why it stopped, and how to step it.
>  
> -   Copyright (C) 1986-2021 Free Software Foundation, Inc.
> +   Copyright (C) 1986-2022 Free Software Foundation, Inc.
>  
>     This file is part of GDB.
>  
> @@ -686,4 +686,7 @@ extern struct inferior *add_inferior_with_spaces (void);
>  /* Print the current selected inferior.  */
>  extern void print_selected_inferior (struct ui_out *uiout);
>  
> +extern void switch_to_inferior_and_push_target (inferior *new_inf,
> +            bool no_connection, inferior *org_inf);
> +
>  #endif /* !defined (INFERIOR_H) */
> diff --git a/gdb/mi/mi-main.c b/gdb/mi/mi-main.c
> index e38520a98e6..65c0aa5be0b 100644
> --- a/gdb/mi/mi-main.c
> +++ b/gdb/mi/mi-main.c
> @@ -1,6 +1,6 @@
>  /* MI Command Set.
>  
> -   Copyright (C) 2000-2021 Free Software Foundation, Inc.
> +   Copyright (C) 2000-2022 Free Software Foundation, Inc.
>  
>     Contributed by Cygnus Solutions (a Red Hat company).
>  
> @@ -1702,6 +1702,8 @@ mi_cmd_add_inferior (const char *command, char **argv, int argc)
>  
>    inf = add_inferior_with_spaces ();
>  
> +  switch_to_inferior_and_push_target (inf, false, current_inferior ());
> +
>    current_uiout->field_fmt ("inferior", "i%d", inf->num);
>  }
>  
> -- 
> 2.31.1