Remove unchecked casts to mi_interp

Simon noticed a crash that could be caused via new Python
gdb.execute_mi function.  Looking into this, I found a few unchecked
casts to mi_interp, like:

-  struct mi_interp *mi = (struct mi_interp *) command_interp ();

This patch replaces all such casts with safer variants.

For -gdb-exit and mi_load_progress, I chose to have the functions
simply not generate any output.  It didn't seem useful to do so.

Some casts I eliminated by adding a parameter to a function.  Then, in
mi_execute_command, I changed the code to use
gdb::checked_static_cast.  This is appropriate because this particular
overload can only be called by the MI interpreter.

There does not seem to be a very good way to test -gdb-exit.

Regression tested on x86-64 Fedora 36.

1 files changed, 0 insertions, 9 deletions

diff --git a/gdb/mi/mi-interp.c b/gdb/mi/mi-interp.c
index a8de62b..0e51c88 100644
--- a/gdb/mi/mi-interp.c
+++ b/gdb/mi/mi-interp.c
@@ -72,15 +72,6 @@ display_mi_prompt (struct mi_interp *mi)
   ui->prompt_state = PROMPTED;
 }
 
-/* Returns the INTERP's data cast as mi_interp if INTERP is an MI, and
-   returns NULL otherwise.  */
-
-static struct mi_interp *
-as_mi_interp (struct interp *interp)
-{
-  return dynamic_cast<mi_interp *> (interp);
-}
-
 void
 mi_interp::on_command_error ()
 {