gdb: remove language_auto

I think that the language_auto enumerator and the auto_language class
can be removed.  There isn't really an "auto" language, it's only a
construct of the "set language" command to say "pick the appropriate
language automatically".  But "auto" is never the current language.  The
`current_language` points to the current effective language, and the
fact that we're in "auto language" mode is noted by the language_mode
global.

 - Change set_language to handle the "auto" (and "local", which is a
   synonym) early, instead of in the for loop.  I think it makes the two
   cases (auto vs explicit language) more clearly separated anyway.

 - Adjust add_set_language_command to hard-code the "auto" string,
   instead of using the "auto" language definition.

 - Remove auto_language, rename auto_or_unknown_language to
   unknown_language and move the bits of the existing unknown_language
   in there.

 - Remove the set_language at the end of _initialize_language.  I think
   it's not needed, because we call set_language in gdb_init, after all
   _initialize functions are called.  There is some chance that an
   _initialize function that runs after _initialize_language implicitly
   depends on current_language being set, but my testsuite runs haven't
   found anything like that.

 - Use language_unknown instead of language_auto when creating a minimal
   symbol (minimal_symbol_reader::record_full).  I think that this value
   is used to indicate that we don't know the symbol of the minimal
   symbol (yet), so language_unknown makes sense to me.  Update a
   condition accordingly in ada-lang.c.  symbol_find_demangled_name also
   appears to "normalize" this value from "unknown" to "auto", remove
   that part and update the condition to just check for
   language_unknown.

Change-Id: I47bcd6c15f607d9818f2e6e413053c2dc8ec5034
Reviewed-By: Tom Tromey <tom@tromey.com>

1 files changed, 2 insertions, 5 deletions

diff --git a/gdb/symtab.c b/gdb/symtab.c
index 6b6905d..9e1e8e9 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -887,10 +887,7 @@ symbol_find_demangled_name (struct general_symbol_info *gsymbol,
   gdb::unique_xmalloc_ptr<char> demangled;
   int i;
 
-  if (gsymbol->language () == language_unknown)
-    gsymbol->m_language = language_auto;
-
-  if (gsymbol->language () != language_auto)
+  if (gsymbol->language () != language_unknown)
     {
       const struct language_defn *lang = language_def (gsymbol->language ());
 
@@ -1028,7 +1025,7 @@ general_symbol_info::compute_and_set_names (gdb::string_view linkage_name,
       (*slot)->demangled = std::move (demangled_name);
       (*slot)->language = language ();
     }
-  else if (language () == language_unknown || language () == language_auto)
+  else if (language () == language_unknown)
     m_language = (*slot)->language;
 
   m_name = (*slot)->mangled.data ();