Merge remote-tracking branch 'origin/maint'

* origin/maint:
  glr.cc: fix a clang warning
  maint: update copyright years
  build: fix VPATH issue
  build: avoid clang's colored diagnostics in the test suite
  tests: please clang and use ".cc", not ".c", for C++ input
  gnulib: update
  skeletons: avoid empty switch constructs
  lalr1.cc: fix compiler warnings
  yacc.c: do not use __attribute__ unprotected
  tests: style changes

data/lalr1.cc

@@ -40,7 +40,6 @@ m4_define([b4_integral_parser_table_define],
   };dnl
 ])
 
-
 # b4_symbol_value_template(VAL, [TYPE])
 # -------------------------------------
 # Same as b4_symbol_value, but used in a template method.  It makes
@@ -205,6 +204,10 @@ b4_location_define])])[
     void error (const syntax_error& err);
 
   private:
+    /// This class is not copyable.
+    ]b4_parser_class_name[ (const ]b4_parser_class_name[&);
+    ]b4_parser_class_name[& operator= (const ]b4_parser_class_name[&);
+
     /// State numbers.
     typedef int state_type;
 
@@ -595,13 +598,7 @@ m4_if(b4_prefix, [yy], [],
       YY_SYMBOL_PRINT (yymsg, yysym);]b4_variant_if([], [
 
     // User destructor.
-    symbol_number_type yytype = yysym.type_get ();
-    switch (yytype)
-      {
-]b4_symbol_foreach([b4_symbol_destructor])dnl
-[       default:
-          break;
-      }])[
+    b4_symbol_actions([destructor], [yysym.type_get ()])])[
   }
 
 #if ]b4_api_PREFIX[DEBUG
@@ -616,12 +613,7 @@ m4_if(b4_prefix, [yy], [],
     yyo << (yytype < yyntokens_ ? "token" : "nterm")
         << ' ' << yytname_[yytype] << " ("]b4_locations_if([
         << yysym.location << ": "])[;
-    switch (yytype)
-      {
-]b4_symbol_foreach([b4_symbol_printer])dnl
-[       default:
-          break;
-      }
+    ]b4_symbol_actions([printer])[
     yyo << ')';
   }
 #endif
@@ -741,7 +733,7 @@ b4_dollar_popdef])[]dnl
        yynewstate, since the latter expects the semantical and the
        location values to have been already stored, initialize these
        stacks with a primary value.  */
-    yystack_ = stack_type (0);
+    yystack_.clear ();
     yypush_ (YY_NULL, 0, yyla);
 
     // A new symbol was pushed on the stack.