From: Bruno Haible <bruno@clisp.org>
Date: Sun, 6 Sep 2020 23:08:11 +0000 (+0200)
Subject: Fix "warning: unannotated fall-through between switch labels".
X-Git-Tag: v0.21.1~46
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e90c28ec9b8711d3eb456757a822e8064021f461;p=thirdparty%2Fgettext.git

Fix "warning: unannotated fall-through between switch labels".

* autogen.sh (GNULIB_MODULES_RUNTIME_FOR_SRC, GNULIB_MODULES_TOOLS_FOR_SRC,
GNULIB_MODULES_LIBGETTEXTPO): Add 'attribute'.
* libtextstyle/autogen.sh (GNULIB_MODULES): Likewise.
* gettext-runtime/intl/plural.y: Include attribute.h. Use FALLTHROUGH annotated
empty statements instead of /* FALLTHROUGH */ comments.
* gettext-runtime/src/gettext.c: Likewise.
* gettext-runtime/src/ngettext.c: Likewise.
* gettext-tools/src/format-boost.c: Likewise.
* gettext-tools/src/read-stringtable.c: Likewise.
* gettext-tools/src/write-csharp.c: Likewise.
* gettext-tools/src/write-java.c: Likewise.
* gettext-tools/src/write-po.c: Likewise.
* gettext-tools/src/x-awk.c: Likewise.
* gettext-tools/src/x-c.c: Likewise.
* gettext-tools/src/x-csharp.c: Likewise.
* gettext-tools/src/x-elisp.c: Likewise.
* gettext-tools/src/x-java.c: Likewise.
* gettext-tools/src/x-javascript.c: Likewise.
* gettext-tools/src/x-librep.c: Likewise.
* gettext-tools/src/x-lisp.c: Likewise.
* gettext-tools/src/x-perl.c: Likewise.
* gettext-tools/src/x-php.c: Likewise.
* gettext-tools/src/x-python.c: Likewise.
* gettext-tools/src/x-scheme.c: Likewise.
* gettext-tools/src/x-sh.c: Likewise.
* gettext-tools/src/x-smalltalk.c: Likewise.
* gettext-tools/src/x-tcl.c: Likewise.
* gettext-tools/src/x-vala.c: Likewise.
* gettext-tools/src/x-ycp.c: Likewise.
* gettext-tools/tests/tstgettext.c: Likewise.
* gettext-tools/tests/tstngettext.c: Likewise.
* libtextstyle/gnulib-local/lib/tparm.c: Likewise.
* gettext-runtime/src/escapes.h: Use FALLTHROUGH annotated empty statements
instead of /* FALLTHROUGH */ comments.
---

diff --git a/autogen.sh b/autogen.sh
index 0d62f61f8..b896c3f1e 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -70,6 +70,7 @@ if ! $skip_gnulib; then
   # In gettext-runtime:
   GNULIB_MODULES_RUNTIME_FOR_SRC='
     atexit
+    attribute
     basename-lgpl
     binary-io
     closeout
@@ -121,6 +122,7 @@ if ! $skip_gnulib; then
   GNULIB_MODULES_TOOLS_FOR_SRC='
     alloca-opt
     atexit
+    attribute
     backupfile
     basename-lgpl
     binary-io
@@ -301,8 +303,9 @@ if ! $skip_gnulib; then
      done` \
     $GNULIB_MODULES_TOOLS_FOR_LIBGREP || exit $?
   # In gettext-tools/libgettextpo:
-  # This is a subset of the GNULIB_MODULES_FOR_SRC.
+  # This is a subset of the GNULIB_MODULES_TOOLS_FOR_SRC.
   GNULIB_MODULES_LIBGETTEXTPO='
+    attribute
     basename-lgpl
     close
     c-ctype
diff --git a/gettext-runtime/intl/plural.y b/gettext-runtime/intl/plural.y
index 676232e10..be78cebf8 100644
--- a/gettext-runtime/intl/plural.y
+++ b/gettext-runtime/intl/plural.y
@@ -24,6 +24,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include "plural-exp.h"
+#include "attribute.h"
 
 /* The main function generated by the parser is called __gettextparse,
    but we want it to be called PLURAL_PARSE.  */
@@ -210,13 +211,13 @@ FREE_EXPRESSION (struct expression *exp)
     {
     case 3:
       FREE_EXPRESSION (exp->val.args[2]);
-      /* FALLTHROUGH */
+      FALLTHROUGH;
     case 2:
       FREE_EXPRESSION (exp->val.args[1]);
-      /* FALLTHROUGH */
+      FALLTHROUGH;
     case 1:
       FREE_EXPRESSION (exp->val.args[0]);
-      /* FALLTHROUGH */
+      FALLTHROUGH;
     default:
       break;
     }
diff --git a/gettext-runtime/src/escapes.h b/gettext-runtime/src/escapes.h
index acda05403..2af737560 100644
--- a/gettext-runtime/src/escapes.h
+++ b/gettext-runtime/src/escapes.h
@@ -1,5 +1,5 @@
 /* Expand escape sequences in a string.
-   Copyright (C) 1995-1997, 2000-2007, 2012, 2018-2019 Free Software
+   Copyright (C) 1995-1997, 2000-2007, 2012, 2018-2020 Free Software
    Foundation, Inc.
    Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, May 1995.
 
@@ -112,7 +112,7 @@ expand_escapes (const char *str, bool *backslash_c_seen)
                   ++cp;
                   break;
                 }
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             default:
               *rp++ = '\\';
               break;
diff --git a/gettext-runtime/src/gettext.c b/gettext-runtime/src/gettext.c
index 99fd82d6a..4773fe5f0 100644
--- a/gettext-runtime/src/gettext.c
+++ b/gettext-runtime/src/gettext.c
@@ -27,6 +27,7 @@
 #include <string.h>
 #include <locale.h>
 
+#include "attribute.h"
 #include "noreturn.h"
 #include "closeout.h"
 #include "error.h"
@@ -160,7 +161,7 @@ There is NO WARRANTY, to the extent permitted by law.\n\
 
           case 2:
             domain = argv[optind++];
-            /* FALLTHROUGH */
+            FALLTHROUGH;
 
           case 1:
             break;
diff --git a/gettext-runtime/src/ngettext.c b/gettext-runtime/src/ngettext.c
index d10f2c3c7..c0b3ca506 100644
--- a/gettext-runtime/src/ngettext.c
+++ b/gettext-runtime/src/ngettext.c
@@ -26,6 +26,7 @@
 #include <locale.h>
 #include <errno.h>
 
+#include "attribute.h"
 #include "noreturn.h"
 #include "closeout.h"
 #include "error.h"
@@ -143,7 +144,7 @@ There is NO WARRANTY, to the extent permitted by law.\n\
 
     case 4:
       domain = argv[optind++];
-      /* FALLTHROUGH */
+      FALLTHROUGH;
 
     case 3:
       break;
diff --git a/gettext-tools/src/format-boost.c b/gettext-tools/src/format-boost.c
index 4cf023cee..3f3b9781e 100644
--- a/gettext-tools/src/format-boost.c
+++ b/gettext-tools/src/format-boost.c
@@ -22,6 +22,7 @@
 #include <stdbool.h>
 #include <stdlib.h>
 
+#include "attribute.h"
 #include "format.h"
 #include "c-ctype.h"
 #include "xalloc.h"
@@ -417,7 +418,7 @@ format_parse (const char *format, bool translated, char *fdi,
                         type = FAT_ANY;
                         break;
                       }
-                    /*FALLTHROUGH*/
+                    FALLTHROUGH;
                   default:
                     --format;
                     if (*format == '\0')
diff --git a/gettext-tools/src/read-stringtable.c b/gettext-tools/src/read-stringtable.c
index 5e5c6f915..7a690dc41 100644
--- a/gettext-tools/src/read-stringtable.c
+++ b/gettext-tools/src/read-stringtable.c
@@ -1,5 +1,5 @@
 /* Reading NeXTstep/GNUstep .strings files.
-   Copyright (C) 2003, 2005-2007, 2009, 2019 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2005-2007, 2009, 2019-2020 Free Software Foundation, Inc.
    Written by Bruno Haible <bruno@clisp.org>, 2003.
 
    This program is free software: you can redistribute it and/or modify
@@ -29,6 +29,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "error.h"
 #include "error-progname.h"
 #include "read-catalog-abstract.h"
@@ -639,7 +640,7 @@ phase4_getc ()
                                       && !seen_newline);
                     break;
                   }
-                /* FALLTHROUGH */
+                FALLTHROUGH;
 
               default:
                 last_was_star = false;
diff --git a/gettext-tools/src/write-csharp.c b/gettext-tools/src/write-csharp.c
index 1a238da79..460ab8cd0 100644
--- a/gettext-tools/src/write-csharp.c
+++ b/gettext-tools/src/write-csharp.c
@@ -70,6 +70,7 @@
 # define S_IXOTH (S_IXUSR >> 6)
 #endif
 
+#include "attribute.h"
 #include "c-ctype.h"
 #include "relocatable.h"
 #include "error.h"
@@ -402,7 +403,7 @@ write_csharp_expression (FILE *stream, const struct expression *exp, bool as_boo
               fprintf (stream, ")");
               return;
             }
-          /*FALLTHROUGH*/
+          FALLTHROUGH;
         case var:
         case mult:
         case divide:
diff --git a/gettext-tools/src/write-java.c b/gettext-tools/src/write-java.c
index 0b0b13216..970aae6f0 100644
--- a/gettext-tools/src/write-java.c
+++ b/gettext-tools/src/write-java.c
@@ -53,6 +53,7 @@
 # define S_IXUSR 00100
 #endif
 
+#include "attribute.h"
 #include "c-ctype.h"
 #include "error.h"
 #include "xerror.h"
@@ -624,7 +625,7 @@ write_java_expression (FILE *stream, const struct expression *exp, bool as_boole
               fprintf (stream, ")");
               return;
             }
-          /*FALLTHROUGH*/
+          FALLTHROUGH;
         case var:
         case mult:
         case divide:
diff --git a/gettext-tools/src/write-po.c b/gettext-tools/src/write-po.c
index adfa55669..4338e8ef4 100644
--- a/gettext-tools/src/write-po.c
+++ b/gettext-tools/src/write-po.c
@@ -1,5 +1,5 @@
 /* GNU gettext - internationalization aids
-   Copyright (C) 1995-1998, 2000-2010, 2012, 2014-2015, 2018-2019 Free Software
+   Copyright (C) 1995-1998, 2000-2010, 2012, 2014-2015, 2018-2020 Free Software
    Foundation, Inc.
 
    This file was written by Peter Miller <millerp@canb.auug.org.au>
@@ -37,6 +37,7 @@
 
 #include <textstyle.h>
 
+#include "attribute.h"
 #include "c-ctype.h"
 #include "po-charset.h"
 #include "format.h"
@@ -79,7 +80,7 @@ make_format_description_string (enum is_format is_format, const char *lang,
           sprintf (result, "possible-%s-format", lang);
           break;
         }
-      /* FALLTHROUGH */
+      FALLTHROUGH;
     case yes_according_to_context:
     case yes:
       sprintf (result, "%s-format", lang);
diff --git a/gettext-tools/src/x-awk.c b/gettext-tools/src/x-awk.c
index af066ff15..c2b8ddcd8 100644
--- a/gettext-tools/src/x-awk.c
+++ b/gettext-tools/src/x-awk.c
@@ -1,5 +1,5 @@
 /* xgettext awk backend.
-   Copyright (C) 2002-2003, 2005-2009, 2018-2019 Free Software Foundation, Inc.
+   Copyright (C) 2002-2003, 2005-2009, 2018-2020 Free Software Foundation, Inc.
 
    This file was written by Bruno Haible <haible@clisp.cons.org>, 2002.
 
@@ -29,6 +29,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "xgettext.h"
 #include "xg-pos.h"
@@ -401,7 +402,7 @@ x_awk_lex (token_ty *tp)
              FIXME: Newlines after any of ',' '{' '?' ':' '||' '&&' 'do' 'else'
              does *not* introduce a fresh statement.  */
           prefer_division_over_regexp = false;
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case '\t':
         case ' ':
           /* Ignore whitespace and comments.  */
@@ -428,7 +429,7 @@ x_awk_lex (token_ty *tp)
                 return;
               }
           }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
         case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
         case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R':
@@ -645,7 +646,7 @@ x_awk_lex (token_ty *tp)
               prefer_division_over_regexp = false;
               return;
             }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
 
         default:
           /* We could carefully recognize each of the 2 and 3 character
diff --git a/gettext-tools/src/x-c.c b/gettext-tools/src/x-c.c
index 08edb12b1..0f19f9665 100644
--- a/gettext-tools/src/x-c.c
+++ b/gettext-tools/src/x-c.c
@@ -30,6 +30,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "rc-str-list.h"
 #include "xgettext.h"
@@ -664,7 +665,7 @@ phase1_ungetc (int c)
 
     case '\n':
       --line_number;
-      /* FALLTHROUGH */
+      FALLTHROUGH;
 
     default:
       if (phase1_pushback_length == SIZEOF (phase1_pushback))
@@ -882,7 +883,7 @@ phase4_getc ()
                   comment_line_end (2);
                   break;
                 }
-              /* FALLTHROUGH */
+              FALLTHROUGH;
 
             default:
               last_was_star = false;
@@ -1344,7 +1345,7 @@ phase5_get (token_ty *tp)
                           error (0, 0, _("%s:%d: warning: a double-quote in the delimiter of a raw string literal is unsupported"),
                                  logical_file_name, starting_line_number);
                           error_with_progname = true;
-                          /* FALLTHROUGH */
+                          FALLTHROUGH;
                         default:
                           valid_delimiter_char = false;
                           break;
@@ -1450,7 +1451,7 @@ phase5_get (token_ty *tp)
                   tp->type = token_type_symbol;
                   return;
                 }
-              /* FALLTHROUGH */
+              FALLTHROUGH;
 
             default:
               phase4_ungetc (c);
@@ -1482,7 +1483,7 @@ phase5_get (token_ty *tp)
           c = '.';
           break;
         }
-      /* FALLTHROUGH */
+      FALLTHROUGH;
 
     case '0': case '1': case '2': case '3': case '4':
     case '5': case '6': case '7': case '8': case '9':
@@ -1505,7 +1506,7 @@ phase5_get (token_ty *tp)
             case 'P':
               /* In C99 and C++17, 'p' and 'P' can be used as an exponent
                  marker.  */
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case 'e':
             case 'E':
               if (bufpos >= bufmax)
@@ -1586,7 +1587,7 @@ phase5_get (token_ty *tp)
                       break;
                     }
                 }
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             default:
               phase4_ungetc (c);
               break;
@@ -1703,7 +1704,7 @@ phase5_get (token_ty *tp)
           tp->comment = add_reference (savable_comment);
           return;
         }
-      /* FALLTHROUGH */
+      FALLTHROUGH;
 
     default:
       /* We could carefully recognize each of the 2 and 3 character
@@ -2145,7 +2146,7 @@ x_c_lex (xgettext_token_ty *tp)
 
         case token_type_objc_special:
           drop_reference (token.comment);
-          /* FALLTHROUGH */
+          FALLTHROUGH;
 
         default:
           last_non_comment_line = newline_count;
diff --git a/gettext-tools/src/x-csharp.c b/gettext-tools/src/x-csharp.c
index 5cf72adbb..13d4a5310 100644
--- a/gettext-tools/src/x-csharp.c
+++ b/gettext-tools/src/x-csharp.c
@@ -28,6 +28,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "rc-str-list.h"
 #include "xgettext.h"
@@ -620,7 +621,7 @@ phase4_getc ()
                   comment_line_end (2);
                   break;
                 }
-              /* FALLTHROUGH */
+              FALLTHROUGH;
 
             default:
               last_was_star = false;
@@ -1496,7 +1497,7 @@ phase6_get (token_ty *tp)
         case UNL:
           if (last_non_comment_line > last_comment_line)
             savable_comment_reset ();
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case ' ':
         case '\t':
         case '\f':
@@ -1536,7 +1537,7 @@ phase6_get (token_ty *tp)
               tp->type = token_type_dot;
               return;
             }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
 
         case '0': case '1': case '2': case '3': case '4':
         case '5': case '6': case '7': case '8': case '9':
@@ -1651,7 +1652,7 @@ phase6_get (token_ty *tp)
               tp->type = token_type_string_literal;
               return;
             }
-          /* FALLTHROUGH, so that @identifier is recognized.  */
+          FALLTHROUGH; /* so that @identifier is recognized.  */
 
         default:
           if (c == '\\')
diff --git a/gettext-tools/src/x-elisp.c b/gettext-tools/src/x-elisp.c
index b29fce5d0..ae0372d5b 100644
--- a/gettext-tools/src/x-elisp.c
+++ b/gettext-tools/src/x-elisp.c
@@ -29,6 +29,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "xgettext.h"
 #include "xg-pos.h"
@@ -527,7 +528,7 @@ do_getc_escaped (int c, bool in_string)
       if (c != '-')
         /* Invalid input.  But be tolerant.  */
         return c;
-      /*FALLTHROUGH*/
+      FALLTHROUGH;
     case '^':
       c = do_getc ();
       if (c == EOF)
@@ -1188,7 +1189,7 @@ read_object (struct object *op, bool first_in_list, bool new_backquote_flag,
                 }
             }
           c = '.';
-          /*FALLTHROUGH*/
+          FALLTHROUGH;
         default:
         default_label:
           if (c <= ' ') /* FIXME: Assumes ASCII compatible encoding */
diff --git a/gettext-tools/src/x-java.c b/gettext-tools/src/x-java.c
index eff1e6f7f..e89ab95f4 100644
--- a/gettext-tools/src/x-java.c
+++ b/gettext-tools/src/x-java.c
@@ -28,6 +28,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "rc-str-list.h"
 #include "xgettext.h"
@@ -519,7 +520,7 @@ phase4_getc ()
                   comment_line_end (2);
                   break;
                 }
-              /* FALLTHROUGH */
+              FALLTHROUGH;
 
             default:
               last_was_star = false;
@@ -1060,7 +1061,7 @@ phase5_get (token_ty *tp)
         case '\n':
           if (last_non_comment_line > last_comment_line)
             savable_comment_reset ();
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case ' ':
         case '\t':
         case '\f':
@@ -1100,7 +1101,7 @@ phase5_get (token_ty *tp)
               tp->type = token_type_dot;
               return;
             }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
 
         case '0': case '1': case '2': case '3': case '4':
         case '5': case '6': case '7': case '8': case '9':
diff --git a/gettext-tools/src/x-javascript.c b/gettext-tools/src/x-javascript.c
index 54ab51a7b..7545adafb 100644
--- a/gettext-tools/src/x-javascript.c
+++ b/gettext-tools/src/x-javascript.c
@@ -31,6 +31,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "rc-str-list.h"
 #include "xgettext.h"
@@ -601,7 +602,7 @@ phase3_getc ()
                           comment_line_end (2);
                           break;
                         }
-                      /* FALLTHROUGH */
+                      FALLTHROUGH;
 
                     default:
                       last_was_star = false;
@@ -1146,7 +1147,7 @@ phase5_get (token_ty *tp)
         case '\n':
           if (last_non_comment_line > last_comment_line)
             savable_comment_reset ();
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case ' ':
         case '\t':
         case '\f':
@@ -1169,7 +1170,7 @@ phase5_get (token_ty *tp)
                 return;
               }
           }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
         case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
         case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R':
diff --git a/gettext-tools/src/x-librep.c b/gettext-tools/src/x-librep.c
index fc346bf08..d694a0b51 100644
--- a/gettext-tools/src/x-librep.c
+++ b/gettext-tools/src/x-librep.c
@@ -29,6 +29,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "c-ctype.h"
 #include "message.h"
 #include "xgettext.h"
@@ -371,7 +372,7 @@ read_token (struct token *tp, const int *first)
                                 radix = 0;
                               break;
                             }
-                          /*FALLTHROUGH*/
+                          FALLTHROUGH;
                         default:
                           if (exponent && (c == '+' || c == '-'))
                             break;
@@ -752,7 +753,7 @@ read_object (struct object *op, flag_context_ty outer_context)
             if (c != EOF && c != '@')
               do_ungetc (c);
           }
-          /*FALLTHROUGH*/
+          FALLTHROUGH;
         case '\'':
         case '`':
           {
@@ -908,7 +909,7 @@ read_object (struct object *op, flag_context_ty outer_context)
                     }
                   continue;
                 }
-              /*FALLTHROUGH*/
+              FALLTHROUGH;
             case '\'':
             case ':':
               {
diff --git a/gettext-tools/src/x-lisp.c b/gettext-tools/src/x-lisp.c
index 921db484f..0137ffdfb 100644
--- a/gettext-tools/src/x-lisp.c
+++ b/gettext-tools/src/x-lisp.c
@@ -29,6 +29,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "xgettext.h"
 #include "xg-pos.h"
@@ -1127,7 +1128,7 @@ read_object (struct object *op, flag_context_ty outer_context)
                 if (c != EOF && c != '@' && c != '.')
                   do_ungetc (c);
               }
-              /*FALLTHROUGH*/
+              FALLTHROUGH;
             case '\'':
             case '`':
               {
@@ -1230,7 +1231,7 @@ read_object (struct object *op, flag_context_ty outer_context)
                   case '(':
                   case '"':
                     do_ungetc (c);
-                    /*FALLTHROUGH*/
+                    FALLTHROUGH;
                   case '\'':
                   case ':':
                   case '.':
diff --git a/gettext-tools/src/x-perl.c b/gettext-tools/src/x-perl.c
index 58892cddf..7d58fc3b7 100644
--- a/gettext-tools/src/x-perl.c
+++ b/gettext-tools/src/x-perl.c
@@ -29,6 +29,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "rc-str-list.h"
 #include "xgettext.h"
@@ -984,7 +985,7 @@ extract_quotelike_pass3 (token_ty *tp, int error_level)
                   buffer[bufpos++] = '\\';
                   break;
                 }
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             default:
               buffer[bufpos++] = *crs++;
               break;
@@ -1666,7 +1667,7 @@ extract_variable (message_list_ty *mlp, token_ty *tp, int first)
                  treat incorrectly here, is a syntax error.  */
               phase1_ungetc (c2);
             }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
 
         default:
 #if DEBUG_PERL
@@ -2007,7 +2008,7 @@ interpolate_keywords (message_list_ty *mlp, const char *string, int lineno)
               break;
             }
           /* Must be right brace.  */
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case wait_rbrace:
           switch (c)
             {
@@ -2019,7 +2020,7 @@ interpolate_keywords (message_list_ty *mlp, const char *string, int lineno)
               extract_quotelike_pass3 (&token, EXIT_FAILURE);
               remember_a_message (mlp, NULL, token.string, true, false, context,
                                   &pos, NULL, savable_comment, true);
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             default:
               context = null_context;
               state = initial;
@@ -2144,7 +2145,7 @@ x_perl_prelex (message_list_ty *mlp, token_ty *tp)
         case '\n':
           if (last_non_comment_line > last_comment_line)
             savable_comment_reset ();
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case '\t':
         case ' ':
           /* Ignore whitespace.  */
@@ -2181,7 +2182,7 @@ x_perl_prelex (message_list_ty *mlp, token_ty *tp)
                 return;
               }
           }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
         case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
         case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R':
@@ -2615,7 +2616,7 @@ x_perl_prelex (message_list_ty *mlp, token_ty *tp)
               if (c != '/')
                 phase1_ungetc (c);
             }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
 
         default:
           /* We could carefully recognize each of the 2 and 3 character
diff --git a/gettext-tools/src/x-php.c b/gettext-tools/src/x-php.c
index 410790961..78cce8e1d 100644
--- a/gettext-tools/src/x-php.c
+++ b/gettext-tools/src/x-php.c
@@ -28,6 +28,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "rc-str-list.h"
 #include "xgettext.h"
@@ -667,7 +668,7 @@ phase3_getc ()
                         comment_line_end (2);
                         break;
                       }
-                    /* FALLTHROUGH */
+                    FALLTHROUGH;
 
                   default:
                     last_was_star = false;
@@ -802,7 +803,7 @@ phase4_get (token_ty *tp)
         case '\n':
           if (last_non_comment_line > last_comment_line)
             savable_comment_reset ();
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case ' ':
         case '\t':
         case '\r':
diff --git a/gettext-tools/src/x-python.c b/gettext-tools/src/x-python.c
index 1dee06100..4c95797f7 100644
--- a/gettext-tools/src/x-python.c
+++ b/gettext-tools/src/x-python.c
@@ -30,6 +30,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "rc-str-list.h"
 #include "xgettext.h"
@@ -1223,7 +1224,7 @@ phase5_get (token_ty *tp)
                 return;
               }
           }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
         case 'G': case 'H': case 'I': case 'J': case 'K': case 'L':
         case 'M': case 'N': case 'O': case 'P': case 'Q':
diff --git a/gettext-tools/src/x-scheme.c b/gettext-tools/src/x-scheme.c
index f29bfe5db..f879ab026 100644
--- a/gettext-tools/src/x-scheme.c
+++ b/gettext-tools/src/x-scheme.c
@@ -29,6 +29,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "xgettext.h"
 #include "xg-pos.h"
@@ -830,7 +831,7 @@ read_object (struct object *op, flag_context_ty outer_context)
             if (c != EOF && c != '@')
               do_ungetc (c);
           }
-          /*FALLTHROUGH*/
+          FALLTHROUGH;
         case '\'':
         case '`':
           {
@@ -1220,7 +1221,7 @@ read_object (struct object *op, flag_context_ty outer_context)
                 while (c >= '0' && c <= '9');
                 /* c should be one of {'a'|'b'|'c'|'e'|'i'|'s'|'u'}.
                    But be tolerant.  */
-                /*FALLTHROUGH*/
+                FALLTHROUGH;
               case '\'': /* boot-9.scm */
               case '.': /* boot-9.scm */
               case ',': /* srfi-10.scm */
@@ -1270,7 +1271,7 @@ read_object (struct object *op, flag_context_ty outer_context)
               }
             seen_underscore_prefix = true;
           }
-          /*FALLTHROUGH*/
+          FALLTHROUGH;
 
         case '"':
           {
diff --git a/gettext-tools/src/x-sh.c b/gettext-tools/src/x-sh.c
index 2b0dedc12..a3f70086b 100644
--- a/gettext-tools/src/x-sh.c
+++ b/gettext-tools/src/x-sh.c
@@ -29,6 +29,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "xgettext.h"
 #include "xg-pos.h"
@@ -222,7 +223,7 @@ phase1_ungetc (int c)
 
     case '\n':
       --line_number;
-      /* FALLTHROUGH */
+      FALLTHROUGH;
 
     default:
       if (phase1_pushback_length == SIZEOF (phase1_pushback))
@@ -718,7 +719,7 @@ phase2_ungetc (int c)
 
     case '\n':
       --line_number;
-      /* FALLTHROUGH */
+      FALLTHROUGH;
 
     default:
       if (phase2_pushback_length == SIZEOF (phase2_pushback))
diff --git a/gettext-tools/src/x-smalltalk.c b/gettext-tools/src/x-smalltalk.c
index d84b307eb..86f6a4ba4 100644
--- a/gettext-tools/src/x-smalltalk.c
+++ b/gettext-tools/src/x-smalltalk.c
@@ -27,6 +27,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "xgettext.h"
 #include "xg-pos.h"
@@ -237,7 +238,7 @@ phase2_get (token_ty *tp)
         case '\n':
           if (last_non_comment_line > last_comment_line)
             savable_comment_reset ();
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case ' ':
         case '\t':
         case '\r':
diff --git a/gettext-tools/src/x-tcl.c b/gettext-tools/src/x-tcl.c
index 6b2b36cf7..f7f784684 100644
--- a/gettext-tools/src/x-tcl.c
+++ b/gettext-tools/src/x-tcl.c
@@ -31,6 +31,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "xgettext.h"
 #include "xg-pos.h"
@@ -220,7 +221,7 @@ phase1_ungetc (int c)
     case '\n':
     case BS_NL:
       --line_number;
-      /* FALLTHROUGH */
+      FALLTHROUGH;
 
     default:
       if (phase1_pushback_length == SIZEOF (phase1_pushback))
diff --git a/gettext-tools/src/x-vala.c b/gettext-tools/src/x-vala.c
index d807f5a6c..e2754f73d 100644
--- a/gettext-tools/src/x-vala.c
+++ b/gettext-tools/src/x-vala.c
@@ -30,6 +30,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "rc-str-list.h"
 #include "xgettext.h"
@@ -296,7 +297,7 @@ phase2_getc ()
                   comment_line_end (2);
                   break;
                 }
-              /* FALLTHROUGH */
+              FALLTHROUGH;
 
             default:
               last_was_star = false;
@@ -670,7 +671,7 @@ phase3_get (token_ty *tp)
         case '\n':
           if (last_non_comment_line > last_comment_line)
             savable_comment_reset ();
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case ' ':
         case '\f':
         case '\t':
@@ -748,7 +749,7 @@ phase3_get (token_ty *tp)
               c = '.';
               break;
             }
-          /* FALLTHROUGH */
+          FALLTHROUGH;
 
         case '0': case '1': case '2': case '3': case '4':
         case '5': case '6': case '7': case '8': case '9':
@@ -845,7 +846,7 @@ phase3_get (token_ty *tp)
               return;
             }
           template = true;
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case '"':
           {
             struct mixed_string_buffer msb;
diff --git a/gettext-tools/src/x-ycp.c b/gettext-tools/src/x-ycp.c
index 5097b5748..4f6d16871 100644
--- a/gettext-tools/src/x-ycp.c
+++ b/gettext-tools/src/x-ycp.c
@@ -29,6 +29,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "attribute.h"
 #include "message.h"
 #include "rc-str-list.h"
 #include "xgettext.h"
@@ -245,7 +246,7 @@ phase2_getc ()
                       savable_comment_add (buffer);
                       break;
                     }
-                  /* FALLTHROUGH */
+                  FALLTHROUGH;
 
                 default:
                   last_was_star = false;
@@ -445,7 +446,7 @@ phase5_get (token_ty *tp)
         case '\n':
           if (last_non_comment_line > last_comment_line)
             savable_comment_reset ();
-          /* FALLTHROUGH */
+          FALLTHROUGH;
         case '\r':
         case '\t':
         case ' ':
diff --git a/gettext-tools/tests/tstgettext.c b/gettext-tools/tests/tstgettext.c
index e473874fc..a855783b0 100644
--- a/gettext-tools/tests/tstgettext.c
+++ b/gettext-tools/tests/tstgettext.c
@@ -27,6 +27,7 @@
 #include <string.h>
 #include <locale.h>
 
+#include "attribute.h"
 #include "noreturn.h"
 #include "closeout.h"
 #include "error.h"
@@ -141,7 +142,7 @@ main (int argc, char *argv[])
             break;
           }
       }
-      /*FALLTHROUGH*/
+      FALLTHROUGH;
     default:
       usage (EXIT_FAILURE);
     }
@@ -184,7 +185,7 @@ There is NO WARRANTY, to the extent permitted by law.\n\
 
           case 2:
             domain = argv[optind++];
-            /* FALLTHROUGH */
+            FALLTHROUGH;
 
           case 1:
             break;
diff --git a/gettext-tools/tests/tstngettext.c b/gettext-tools/tests/tstngettext.c
index 012399a3d..e9ce5c967 100644
--- a/gettext-tools/tests/tstngettext.c
+++ b/gettext-tools/tests/tstngettext.c
@@ -27,6 +27,7 @@
 #include <locale.h>
 #include <errno.h>
 
+#include "attribute.h"
 #include "noreturn.h"
 #include "closeout.h"
 #include "error.h"
@@ -118,7 +119,7 @@ main (int argc, char *argv[])
             break;
           }
       }
-      /*FALLTHROUGH*/
+      FALLTHROUGH;
     default:
       usage (EXIT_FAILURE);
     }
diff --git a/libtextstyle/autogen.sh b/libtextstyle/autogen.sh
index 740dd6755..620875195 100755
--- a/libtextstyle/autogen.sh
+++ b/libtextstyle/autogen.sh
@@ -4,7 +4,7 @@
 # also regenerates all aclocal.m4, config.h.in, Makefile.in, configure files
 # with new versions of autoconf or automake.
 #
-# This script requires autoconf-2.63..2.71 and automake-1.11..1.16 in the PATH.
+# This script requires autoconf-2.64..2.71 and automake-1.11..1.16 in the PATH.
 # If not used from a released tarball, it also requires
 #   - the GNULIB_SRCDIR environment variable pointing to a gnulib checkout.
 
@@ -85,6 +85,7 @@ if test $skip_gnulib = false; then
       html-styled-ostream
       noop-styled-ostream
       term-styled-ostream
+    attribute
     filename
     isatty
     largefile
diff --git a/libtextstyle/gnulib-local/lib/tparm.c b/libtextstyle/gnulib-local/lib/tparm.c
index 787667679..8b376a0e2 100644
--- a/libtextstyle/gnulib-local/lib/tparm.c
+++ b/libtextstyle/gnulib-local/lib/tparm.c
@@ -1,5 +1,5 @@
 /* Substitution of parameters in strings from terminal descriptions.
-   Copyright (C) 2006, 2012 Free Software Foundation, Inc.
+   Copyright (C) 2006, 2012, 2020 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
@@ -22,6 +22,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#include "attribute.h"
 #include "c-ctype.h"
 
 #ifdef USE_SCCS_IDS
@@ -331,7 +332,7 @@ tparm (const char *str, ...)
                   sp++;
                   break;
                 }
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case 'C':
               if (*sp == 'C')
                 {
@@ -347,7 +348,7 @@ tparm (const char *str, ...)
                     }
                 }
               fmt = "%c";
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case 'a':
               if (!termcap)
                 return OOPS;
@@ -415,7 +416,7 @@ tparm (const char *str, ...)
               if (fmt == NULL)
                 break;
               sp--;
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case '-':
               if (!termcap)
                 {
@@ -429,7 +430,7 @@ tparm (const char *str, ...)
                   break;
                 }
               fmt = "%c";
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case 's':
               if (termcap && (fmt == NULL || *sp == '-'))
                 {
@@ -449,23 +450,23 @@ tparm (const char *str, ...)
                 }
               if (!termcap)
                 return OOPS;
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case '.':
               if (termcap && fmt == NULL)
                 fmt = "%c";
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case 'd':
               if (termcap && fmt == NULL)
                 fmt = "%d";
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case '2':
               if (termcap && fmt == NULL)
                 fmt = "%02d";
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case '3':
               if (termcap && fmt == NULL)
                 fmt = "%03d";
-              /* FALLTHROUGH */
+              FALLTHROUGH;
             case ':': case ' ': case '#': case 'u':
             case 'x': case 'X': case 'o': case 'c':
             case '0': case '1': case '4': case '5':