c++: remove now-useless operators

Now that symbols behaves properly, we can eliminate special routines
that are no longer needed.

* data/c++.m4, data/glr.cc, data/lalr1.cc, data/variant.hh:
Remove useless assignment operators and copy constructors.
As a consequence, remove useless includes for "abort".

data/c++.m4

@@ -171,9 +171,6 @@ m4_define([b4_public_types_declare],
 
       /// Default constructor.
       inline basic_symbol ();
-]b4_locations_if([
-      /// Constructor.
-      inline basic_symbol (const location_type& l);])[
 
       /// Copy constructor.
       inline basic_symbol (const basic_symbol& other);
@@ -188,8 +185,6 @@ m4_define([b4_public_types_declare],
                            const location_type& l])[);
 
       ~basic_symbol ();
-      /// Assignment operator.
-      inline basic_symbol& operator= (const basic_symbol& other);
 
       /// Destructive move, \a s is emptied into this.
       inline void move (basic_symbol& s);
@@ -199,6 +194,10 @@ m4_define([b4_public_types_declare],
 
       /// The location.
       location_type location;])[
+
+    private:
+      /// Assignment operator.
+      basic_symbol& operator= (const basic_symbol& other);
     };
 
     /// Type access provider for token (enum) based symbols.
@@ -254,19 +253,6 @@ m4_define([b4_public_types_define],
   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol ()
     : value ()
   {}
-]b4_locations_if([
-  template <typename Base>
-  ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (const location_type& l)
-    : value ()
-    , location (l)
-  {}])[
-
-  template <typename Base>
-  ]b4_parser_class_name[::basic_symbol<Base>&
-  ]b4_parser_class_name[::basic_symbol<Base>::operator= (const basic_symbol&)
-  {
-    abort ();
-  }
 
   template <typename Base>
   ]b4_parser_class_name[::basic_symbol<Base>::basic_symbol (const basic_symbol& other)

data/glr.cc

@@ -253,7 +253,6 @@ m4_define([b4_shared_declarations],
 [m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
 b4_percent_code_get([[requires]])[
 
-#include <cstdlib>  // abort
 #include <stdexcept>
 #include <string>
 #include <iostream>]b4_defines_if([

data/lalr1.cc

@@ -146,7 +146,6 @@ b4_variant_if([m4_include(b4_pkgdatadir/[variant.hh])])
 m4_define([b4_shared_declarations],
 [b4_percent_code_get([[requires]])[
 ]b4_parse_assert_if([# include <cassert>])[
-# include <cstdlib>  // abort
 # include <vector>
 # include <iostream>
 # include <stdexcept>
@@ -308,6 +307,7 @@ b4_location_define])])[
       stack_symbol_type ();
       /// Steal the contents from \a sym to build this.
       stack_symbol_type (state_type s, symbol_type& sym);
+      /// Assignment, needed by push_back.
       stack_symbol_type& operator= (const stack_symbol_type& that);
     };
 

data/variant.hh

@@ -72,7 +72,6 @@ m4_map([      b4_symbol_tag_comment], [$@])dnl
 # The needed includes for variants support.
 m4_define([b4_variant_includes],
 [b4_parse_assert_if([[#include <typeinfo>]])[
-#include <cstdlib>  // abort
 #ifndef YYASSERT
 # include <cassert>
 # define YYASSERT assert
@@ -213,19 +212,11 @@ m4_define([b4_variant_define],
       tname = YY_NULL;])[
     }
 
-    /// Prohibit blind copies.
-    private:
-    self_type& operator=(const self_type&)
-    {
-      abort ();
-    }
-
-    variant (const self_type&)
-    {
-      abort ();
-    }
-
   private:
+    /// Prohibit blind copies.
+    self_type& operator=(const self_type&);
+    variant (const self_type&);
+
     /// A buffer large enough to store any of the semantic values.
     /// Long double is chosen as it has the strongest alignment
     /// constraints.