Merge remote-tracking branch 'origin/maint'

* origin/maint:
  maint: post-release administrivia
  version 3.0.4
  gnulib: update
  build: re-enable compiler warnings, and fix them
  tests: c++: fix a C++03 conformance issue
  tests: fix a title
  c++: reserve 200 slots in the parser's stack
  tests: be more robust to unrecognized synclines, and try to recognize xlc
  tests: fix C++ conformance
  build: fix some warnings
  build: avoid infinite recursions on include_next

data/lalr1.cc

@@ -149,10 +149,11 @@ 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 <vector>
+# include <cstdlib> // std::abort
 # include <iostream>
 # include <stdexcept>
-# include <string>]b4_defines_if([[
+# include <string>
+# include <vector>]b4_defines_if([[
 # include "stack.hh"
 ]b4_bison_locations_if([[# include "location.hh"]])])[
 ]b4_variant_if([b4_variant_includes])[
@@ -569,7 +570,10 @@ m4_if(b4_prefix, [yy], [],
   ]b4_parser_class_name[::symbol_number_type
   ]b4_parser_class_name[::by_state::type_get () const
   {
-    return state == empty_state ? empty_symbol : yystos_[state];
+    if (state == empty_state)
+      return empty_symbol;
+    else
+      return yystos_[state];
   }
 
   inline
@@ -622,6 +626,10 @@ m4_if(b4_prefix, [yy], [],
     std::ostream& yyoutput = yyo;
     YYUSE (yyoutput);
     symbol_number_type yytype = yysym.type_get ();
+    // Avoid a (spurious) G++ 4.8 warning about "array subscript is
+    // below array bounds".
+    if (yysym.empty ())
+      std::abort ();
     yyo << (yytype < yyntokens_ ? "token" : "nterm")
         << ' ' << yytname_[yytype] << " ("]b4_locations_if([
         << yysym.location << ": "])[;

data/stack.hh

@@ -32,12 +32,12 @@ m4_define([b4_stack_define],
     stack ()
       : seq_ ()
     {
+      seq_.reserve (200);
     }
 
     stack (unsigned int n)
       : seq_ (n)
-    {
-    }
+    {}
 
     inline
     T&
@@ -114,8 +114,7 @@ m4_define([b4_stack_define],
     slice (const S& stack, unsigned int range)
       : stack_ (stack)
       , range_ (range)
-    {
-    }
+    {}
 
     inline
     const T&