[binutils-gdb] Fix the only incorrect case found by command_structure_invariants selftest.

[gdb-buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT a7b9ceb8b44cd36496e266894075e2af60c3e153 ***

commit a7b9ceb8b44cd36496e266894075e2af60c3e153
Author:     Philippe Waroquiers <philippe.waroquiers@skynet.be>
AuthorDate: Mon May 4 23:02:18 2020 +0200
Commit:     Philippe Waroquiers <philippe.waroquiers@skynet.be>
CommitDate: Fri May 15 22:17:45 2020 +0200

    Fix the only incorrect case found by command_structure_invariants selftest.
    
    The next commit introduces a selftest that detects when the GDB
    command structure does not define a tree when using the pointers
    'next/*prefixlist'.  This test detects one such case, fixed
    by this commit.
    
    The command 'info set' was defined as a specific prefix command,
    but re-using the command list already used for the 'show' command.
    This leads to the command tree 'next/*prefixlist' to not be a tree.
    
    This change defines 'info set ' as an alias, thereby fixing the selftest.
    
    2020-05-15  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
    
            * cli/cli-cmds.c (_initialize_cli_cmds): Define 'info set' as
            an alias of 'show'.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index f91827e4ce..619745e324 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2020-05-15  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
+
+	* cli/cli-cmds.c (_initialize_cli_cmds): Define 'info set' as
+	an alias of 'show'.
+
 2020-05-15  Joel Brobecker  <brobecker@adacore.com>
 
 	* ada-lang.h: (ada_is_gnat_encoded_fixed_point_type): Renames
diff --git a/gdb/cli/cli-cmds.c b/gdb/cli/cli-cmds.c
index 58e9cf3195..c17521b1f6 100644
--- a/gdb/cli/cli-cmds.c
+++ b/gdb/cli/cli-cmds.c
@@ -2209,12 +2209,11 @@ Generic command for showing things about the program being debugged."),
   add_com ("complete", class_obscure, complete_command,
 	   _("List the completions for the rest of the line as a command."));
 
-  add_show_prefix_cmd ("show", class_info, _("\
+  c = add_show_prefix_cmd ("show", class_info, _("\
 Generic command for showing things about the debugger."),
-		       &showlist, "show ", 0, &cmdlist);
+			   &showlist, "show ", 0, &cmdlist);
   /* Another way to get at the same thing.  */
-  add_show_prefix_cmd ("set", class_info, _("Show all GDB settings."),
-		       &showlist, "info set ", 0, &infolist);
+  add_alias_cmd ("set", c, class_info, 0, &infolist);
 
   c = add_com ("with", class_vars, with_command, _("\
 Temporarily set SETTING to VALUE, run COMMAND, and restore SETTING.\n\