gdb: rename gdbarch_tdep struct to fix g++ 4.8 build

After the commit:

  commit 08106042d9f5fdff60c129bf33190639f1a98b2a
  Date:   Thu May 19 13:20:17 2022 +0100

      gdb: move the type cast into gdbarch_tdep

GDB would no longer build using g++ 4.8.  The issue appears to be some
confusion caused by GDB having 'struct gdbarch_tdep', but also a
templated function called 'gdbarch_tdep'.  Prior to the above commit
the gdbarch_tdep function was not templated, and this compiled just
fine.  Note that the above commit compiles just fine with later
versions of g++, so this issue was clearly fixed at some point, though
I've not tried to track down exactly when.

In this commit I propose to fix the g++ 4.8 build problem by renaming
'struct gdbarch_tdep' to 'struct gdbarch_tdep_base'.  This rename
better represents that the struct is only ever used as a base class,
and removes the overloading of the name, which allows GDB to build
with g++ 4.8.

I've also updated the comment on 'struct gdbarch_tdep_base' to fix a
typo, and the comment on the 'gdbarch_tdep' function, to mention that
in maintainer mode a run-time type check is performed.

1 files changed, 1 insertions, 1 deletions

diff --git a/gdb/arch-utils.c b/gdb/arch-utils.c
index 360b8d6..4e55b27 100644
--- a/gdb/arch-utils.c
+++ b/gdb/arch-utils.c
@@ -1200,7 +1200,7 @@ gdbarch_free (struct gdbarch *arch)
 
 /* See gdbarch.h.  */
 
-struct gdbarch_tdep *
+struct gdbarch_tdep_base *
 gdbarch_tdep_1 (struct gdbarch *gdbarch)
 {
   if (gdbarch_debug >= 2)