gdb: Move la_language into the language_defn class

Move the language_data::la_language member variable into the
langage_defn class.

I have not made the la_language member variable a method of
langage_defn simply because of the large number of places that
la_language is referenced throughout GDB.  I have made the new member
variable constant though, so this should prevent accidental
assignment.

In the future we might consider converting la_language to a method,
but right now my goal is to remove the langage_data class, so I'm
happy to leave la_language as a constant member variable.

There should be no user visible changes after this commit.

gdb/ChangeLog:

	* ada-lang.c (ada_language_data): Remove la_language initializer.
	* c-lang.c (c_language_data): Likewise.
	(cplus_language_data): Likewise.
	(asm_language_data): Likewise.
	(minimal_language_data): Likewise.
	* d-lang.c (d_language_data): Likewise.
	* f-lang.c (f_language_data): Likewise.
	* go-lang.c (go_language_data): Likewise.
	* language.c (unknown_language_data): Likewise.
	(auto_language_data): Likewise.
	* language.h (language_data): Remove la_language field.
	(language_defn::language_defn): Initialise la_language field.
	(language_defn::la_language): New member variable.
	* m2-lang.c (m2_language_data): Remove la_language field.
	* objc-lang.c (objc_language_data): Likewise.
	* opencl-lang.c (opencl_language_data): Likewise.
	* p-lang.c (pascal_language_data): Likewise.
	* rust-lang.c (rust_language_data): Likewise.

gdb/ChangeLog

@@ -1,3 +1,24 @@
+2020-09-16  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* ada-lang.c (ada_language_data): Remove la_language initializer.
+	* c-lang.c (c_language_data): Likewise.
+	(cplus_language_data): Likewise.
+	(asm_language_data): Likewise.
+	(minimal_language_data): Likewise.
+	* d-lang.c (d_language_data): Likewise.
+	* f-lang.c (f_language_data): Likewise.
+	* go-lang.c (go_language_data): Likewise.
+	* language.c (unknown_language_data): Likewise.
+	(auto_language_data): Likewise.
+	* language.h (language_data): Remove la_language field.
+	(language_defn::language_defn): Initialise la_language field.
+	(language_defn::la_language): New member variable.
+	* m2-lang.c (m2_language_data): Remove la_language field.
+	* objc-lang.c (objc_language_data): Likewise.
+	* opencl-lang.c (opencl_language_data): Likewise.
+	* p-lang.c (pascal_language_data): Likewise.
+	* rust-lang.c (rust_language_data): Likewise.
+
 2020-09-16  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* ada-lang.c (ada_extensions): Delete, moved into

gdb/ada-lang.c

@@ -13708,7 +13708,6 @@ ada_get_symbol_name_matcher (const lookup_name_info &lookup_name)
 
 extern const struct language_data ada_language_data =
 {
-  language_ada,
   range_check_off,
   case_sensitive_on,            /* Yes, Ada is case-insensitive, but
                                    that's not quite what this means.  */

gdb/c-lang.c

@@ -875,7 +875,6 @@ const struct exp_descriptor exp_descriptor_c =
 
 extern const struct language_data c_language_data =
 {
-  language_c,
   range_check_off,
   case_sensitive_on,
   array_row_major,
@@ -984,7 +983,6 @@ enum cplus_primitive_types {
 
 extern const struct language_data cplus_language_data =
 {
-  language_cplus,
   range_check_off,
   case_sensitive_on,
   array_row_major,
@@ -1196,7 +1194,6 @@ static cplus_language cplus_language_defn;
 
 extern const struct language_data asm_language_data =
 {
-  language_asm,
   range_check_off,
   case_sensitive_on,
   array_row_major,
@@ -1266,7 +1263,6 @@ static asm_language asm_language_defn;
 
 extern const struct language_data minimal_language_data =
 {
-  language_minimal,
   range_check_off,
   case_sensitive_on,
   array_row_major,

gdb/d-lang.c

@@ -128,7 +128,6 @@ enum d_primitive_types {
 
 extern const struct language_data d_language_data =
 {
-  language_d,
   range_check_off,
   case_sensitive_on,
   array_row_major,

gdb/f-lang.c

@@ -486,7 +486,6 @@ static const struct exp_descriptor exp_descriptor_f =
 
 extern const struct language_data f_language_data =
 {
-  language_fortran,
   range_check_on,
   case_sensitive_off,
   array_column_major,

gdb/go-lang.c

@@ -508,7 +508,6 @@ enum go_primitive_types {
 
 extern const struct language_data go_language_data =
 {
-  language_go,
   range_check_off,
   case_sensitive_on,
   array_row_major,

gdb/language.c

@@ -775,7 +775,6 @@ unknown_language_arch_info (struct gdbarch *gdbarch,
 
 extern const struct language_data unknown_language_data =
 {
-  language_unknown,
   range_check_off,
   case_sensitive_on,
   array_row_major,
@@ -911,7 +910,6 @@ static unknown_language unknown_language_defn;
 
 extern const struct language_data auto_language_data =
 {
-  language_auto,
   range_check_off,
   case_sensitive_on,
   array_row_major,

gdb/language.h

@@ -188,10 +188,6 @@ extern const char *default_word_break_characters (void);
 
 struct language_data
   {
-    /* its symtab language-enum (defs.h).  */
-
-    enum language la_language;
-
     /* Default range checking.  */
 
     enum range_check la_range_check;
@@ -253,13 +249,18 @@ struct language_data
 struct language_defn : language_data
 {
   language_defn (enum language lang, const language_data &init_data)
-    : language_data (init_data)
+    : language_data (init_data),
+      la_language (lang)
   {
     /* We should only ever create one instance of each language.  */
     gdb_assert (languages[lang] == nullptr);
     languages[lang] = this;
   }
 
+  /* Which language this is.  */
+
+  const enum language la_language;
+
   /* Name of the language.  */
 
   virtual const char *name () const = 0;

gdb/m2-lang.c

@@ -199,7 +199,6 @@ const struct exp_descriptor exp_descriptor_modula2 =
 
 extern const struct language_data m2_language_data =
 {
-  language_m2,
   range_check_on,
   case_sensitive_on,
   array_row_major,

gdb/objc-lang.c

@@ -323,7 +323,6 @@ static const struct op_print objc_op_print_tab[] =
 
 extern const struct language_data objc_language_data =
 {
-  language_objc,
   range_check_off,
   case_sensitive_on,
   array_row_major,

gdb/opencl-lang.c

@@ -1006,7 +1006,6 @@ const struct exp_descriptor exp_descriptor_opencl =
 /* Constant data representing the OpenCL language.  */
 extern const struct language_data opencl_language_data =
 {
-  language_opencl,
   range_check_off,
   case_sensitive_on,
   array_row_major,

gdb/p-lang.c

@@ -252,7 +252,6 @@ enum pascal_primitive_types {
 
 extern const struct language_data pascal_language_data =
 {
-  language_pascal,
   range_check_on,
   case_sensitive_on,
   array_row_major,

gdb/rust-lang.c

@@ -1901,7 +1901,6 @@ static const struct exp_descriptor exp_descriptor_rust =
 
 extern const struct language_data rust_language_data =
 {
-  language_rust,
   range_check_on,
   case_sensitive_on,
   array_row_major,