[CWEB] Make 'fall thru' comments active.

This is specific for GCC, but totally harmless for any other C compiler:

GCC accepts 'fall thru' comments from the CWEB sources with its option
'-Wimplicit-fallthrough=2', when we push these comments over to the
tangled C code.

git-svn-id: svn://tug.org/texlive/trunk@62584 c570f23f-e606-0410-a88d-b1316a301751

11 files changed, 83 insertions, 59 deletions

diff --git a/Build/source/texk/web2c/ChangeLog b/Build/source/texk/web2c/ChangeLog
index 15ce99f9290..a5821c23dec 100644
--- a/Build/source/texk/web2c/ChangeLog
+++ b/Build/source/texk/web2c/ChangeLog
@@ -1,3 +1,7 @@
+2022-03-10  Andreas Scherer  <https://ascherer.github.io>
+
+	* ctangleboot.cin: Make 'fall thru' comments active.
+
 2022-03-03  Andreas Scherer  <https://ascherer.github.io>
 
 	* cpascal.h,
diff --git a/Build/source/texk/web2c/ctangleboot.cin b/Build/source/texk/web2c/ctangleboot.cin
index 5d0b10ec927..18ba68505ce 100644
--- a/Build/source/texk/web2c/ctangleboot.cin
+++ b/Build/source/texk/web2c/ctangleboot.cin
@@ -274,7 +274,7 @@ extern FILE*active_file;
 extern FILE*check_file;
 
 /*:15*//*116:*/
-#line 504 "cwebdir/ctang-w2c.ch"
+#line 506 "cwebdir/ctang-w2c.ch"
 
 extern char cb_banner[];
 
@@ -540,7 +540,7 @@ ccode['\'']= ord;
 section_text[0]= ' ';
 
 /*:78*//*117:*/
-#line 507 "cwebdir/ctang-w2c.ch"
+#line 509 "cwebdir/ctang-w2c.ch"
 
 strncpy(cb_banner,banner,max_banner-1);
 
@@ -754,11 +754,11 @@ writeloop:/*50:*/
 if(check_for_change){
 fclose(C_file);C_file= NULL;
 /*106:*/
-#line 387 "cwebdir/ctang-w2c.ch"
+#line 389 "cwebdir/ctang-w2c.ch"
 
 if((C_file= fopen(C_file_name,"r"))!=NULL){
 /*107:*/
-#line 394 "cwebdir/ctang-w2c.ch"
+#line 396 "cwebdir/ctang-w2c.ch"
 
 boolean comparison= false;
 
@@ -767,7 +767,7 @@ fatal(_("! Cannot open output file "),check_file_name);
 
 
 /*108:*/
-#line 408 "cwebdir/ctang-w2c.ch"
+#line 410 "cwebdir/ctang-w2c.ch"
 
 do{
 char x[BUFSIZ],y[BUFSIZ];
@@ -777,17 +777,17 @@ comparison= (x_size==y_size)&&!memcmp(x,y,x_size);
 }while(comparison&&!feof(C_file)&&!feof(check_file));
 
 /*:108*/
-#line 401 "cwebdir/ctang-w2c.ch"
+#line 403 "cwebdir/ctang-w2c.ch"
 
 
 fclose(C_file);C_file= NULL;
 fclose(check_file);check_file= NULL;
 
 /*:107*/
-#line 389 "cwebdir/ctang-w2c.ch"
+#line 391 "cwebdir/ctang-w2c.ch"
 
 /*109:*/
-#line 419 "cwebdir/ctang-w2c.ch"
+#line 421 "cwebdir/ctang-w2c.ch"
 
 if(comparison)
 remove(check_file_name);
@@ -797,7 +797,7 @@ rename(check_file_name,C_file_name);
 }
 
 /*:109*/
-#line 390 "cwebdir/ctang-w2c.ch"
+#line 392 "cwebdir/ctang-w2c.ch"
 
 }else
 rename(check_file_name,C_file_name);
@@ -810,7 +810,7 @@ for(an_output_file= end_output_files;an_output_file> cur_out_file;){
 an_output_file--;
 sprint_section_name(output_file_name,*an_output_file);
 if(check_for_change)/*105:*/
-#line 378 "cwebdir/ctang-w2c.ch"
+#line 380 "cwebdir/ctang-w2c.ch"
 {
 if((C_file= fopen(output_file_name,"a"))==NULL)
 fatal(_("! Cannot open output file "),output_file_name);
@@ -841,14 +841,14 @@ flush_buffer();
 if(check_for_change){
 fclose(C_file);C_file= NULL;
 /*110:*/
-#line 432 "cwebdir/ctang-w2c.ch"
+#line 434 "cwebdir/ctang-w2c.ch"
 
 if(0==strcmp("/dev/stdout",output_file_name))
 /*112:*/
-#line 459 "cwebdir/ctang-w2c.ch"
+#line 461 "cwebdir/ctang-w2c.ch"
 {
 /*115:*/
-#line 490 "cwebdir/ctang-w2c.ch"
+#line 492 "cwebdir/ctang-w2c.ch"
 
 char in_buf[BUFSIZ+1];
 int in_size;
@@ -858,7 +858,7 @@ fatal(_("! Cannot open output file "),check_file_name);
 
 
 /*:115*/
-#line 460 "cwebdir/ctang-w2c.ch"
+#line 462 "cwebdir/ctang-w2c.ch"
 
 do{
 in_size= fread(in_buf,sizeof(char),BUFSIZ,check_file);
@@ -867,7 +867,7 @@ fprintf(stdout,"%s",in_buf);
 }while(!feof(check_file));
 fclose(check_file);check_file= NULL;
 /*111:*/
-#line 449 "cwebdir/ctang-w2c.ch"
+#line 451 "cwebdir/ctang-w2c.ch"
 
 if(comparison)
 remove(check_file_name);
@@ -877,19 +877,19 @@ rename(check_file_name,output_file_name);
 }
 
 /*:111*/
-#line 467 "cwebdir/ctang-w2c.ch"
+#line 469 "cwebdir/ctang-w2c.ch"
 
 }
 
 /*:112*/
-#line 434 "cwebdir/ctang-w2c.ch"
+#line 436 "cwebdir/ctang-w2c.ch"
 
 else if(0==strcmp("/dev/stderr",output_file_name))
 /*113:*/
-#line 472 "cwebdir/ctang-w2c.ch"
+#line 474 "cwebdir/ctang-w2c.ch"
 {
 /*115:*/
-#line 490 "cwebdir/ctang-w2c.ch"
+#line 492 "cwebdir/ctang-w2c.ch"
 
 char in_buf[BUFSIZ+1];
 int in_size;
@@ -899,7 +899,7 @@ fatal(_("! Cannot open output file "),check_file_name);
 
 
 /*:115*/
-#line 473 "cwebdir/ctang-w2c.ch"
+#line 475 "cwebdir/ctang-w2c.ch"
 
 do{
 in_size= fread(in_buf,sizeof(char),BUFSIZ,check_file);
@@ -908,7 +908,7 @@ fprintf(stderr,"%s",in_buf);
 }while(!feof(check_file));
 fclose(check_file);check_file= NULL;
 /*111:*/
-#line 449 "cwebdir/ctang-w2c.ch"
+#line 451 "cwebdir/ctang-w2c.ch"
 
 if(comparison)
 remove(check_file_name);
@@ -918,20 +918,20 @@ rename(check_file_name,output_file_name);
 }
 
 /*:111*/
-#line 480 "cwebdir/ctang-w2c.ch"
+#line 482 "cwebdir/ctang-w2c.ch"
 
 }
 
 /*:113*/
-#line 436 "cwebdir/ctang-w2c.ch"
+#line 438 "cwebdir/ctang-w2c.ch"
 
 else if(0==strcmp("/dev/null",output_file_name))
 /*114:*/
-#line 485 "cwebdir/ctang-w2c.ch"
+#line 487 "cwebdir/ctang-w2c.ch"
 {
 boolean comparison= true;
 /*111:*/
-#line 449 "cwebdir/ctang-w2c.ch"
+#line 451 "cwebdir/ctang-w2c.ch"
 
 if(comparison)
 remove(check_file_name);
@@ -941,17 +941,17 @@ rename(check_file_name,output_file_name);
 }
 
 /*:111*/
-#line 487 "cwebdir/ctang-w2c.ch"
+#line 489 "cwebdir/ctang-w2c.ch"
 
 }
 
 /*:114*/
-#line 438 "cwebdir/ctang-w2c.ch"
+#line 440 "cwebdir/ctang-w2c.ch"
 
 else{
 if((C_file= fopen(output_file_name,"r"))!=NULL){
 /*107:*/
-#line 394 "cwebdir/ctang-w2c.ch"
+#line 396 "cwebdir/ctang-w2c.ch"
 
 boolean comparison= false;
 
@@ -960,7 +960,7 @@ fatal(_("! Cannot open output file "),check_file_name);
 
 
 /*108:*/
-#line 408 "cwebdir/ctang-w2c.ch"
+#line 410 "cwebdir/ctang-w2c.ch"
 
 do{
 char x[BUFSIZ],y[BUFSIZ];
@@ -970,17 +970,17 @@ comparison= (x_size==y_size)&&!memcmp(x,y,x_size);
 }while(comparison&&!feof(C_file)&&!feof(check_file));
 
 /*:108*/
-#line 401 "cwebdir/ctang-w2c.ch"
+#line 403 "cwebdir/ctang-w2c.ch"
 
 
 fclose(C_file);C_file= NULL;
 fclose(check_file);check_file= NULL;
 
 /*:107*/
-#line 441 "cwebdir/ctang-w2c.ch"
+#line 443 "cwebdir/ctang-w2c.ch"
 
 /*111:*/
-#line 449 "cwebdir/ctang-w2c.ch"
+#line 451 "cwebdir/ctang-w2c.ch"
 
 if(comparison)
 remove(check_file_name);
@@ -990,7 +990,7 @@ rename(check_file_name,output_file_name);
 }
 
 /*:111*/
-#line 442 "cwebdir/ctang-w2c.ch"
+#line 444 "cwebdir/ctang-w2c.ch"
 
 }else
 rename(check_file_name,output_file_name);
@@ -1153,7 +1153,7 @@ case string:if(out_state==verbatim)out_state= normal;
 else out_state= verbatim;break;
 case'/':C_putc('/');out_state= post_slash;break;
 case'*':if(out_state==post_slash)C_putc(' ');
-
+/* fall through */
 default:C_putc(cur_char);out_state= normal;break;
 }
 }
@@ -1930,7 +1930,7 @@ while(xisspace(*loc)&&loc<limit)loc++;
 loc+= 3;
 if(loc> limit||!xisxdigit(*(loc-3))||!xisxdigit(*(loc-2))
 ||(*(loc-3)>='0'&&*(loc-3)<='7')||!xisspace(*(loc-1)))
-#line 330 "cwebdir/ctang-w2c.ch"
+#line 332 "cwebdir/ctang-w2c.ch"
 err_print(_("! Improper hex number following @l"));
 #line 1529 "cwebdir/ctangle.w"
 
@@ -1942,7 +1942,7 @@ while(xisspace(*loc)&&loc<limit)loc++;
 beg= loc;
 while(loc<limit&&(xisalpha(*loc)||xisdigit(*loc)||*loc=='_'))loc++;
 if(loc-beg>=translit_length)
-#line 336 "cwebdir/ctang-w2c.ch"
+#line 338 "cwebdir/ctang-w2c.ch"
 err_print(_("! Replacement string in @l too long"));
 #line 1539 "cwebdir/ctangle.w"
 
@@ -1964,8 +1964,8 @@ err_print(_("! Double @ should be used in control text"));
 #line 1511 "cwebdir/ctangle.w"
 
 break;
-}
-#line 324 "cwebdir/ctang-w2c.ch"
+#line 325 "cwebdir/ctang-w2c.ch"
+}/* otherwise fall through */
 default:err_print(_("! Double @ should be used in limbo"));
 #line 1515 "cwebdir/ctangle.w"
 
@@ -1979,7 +1979,7 @@ default:err_print(_("! Double @ should be used in limbo"));
 
 void
 print_stats(void){
-#line 349 "cwebdir/ctang-w2c.ch"
+#line 351 "cwebdir/ctang-w2c.ch"
 puts(_("\nMemory usage statistics:"));
 printf(_("%td names (out of %ld)\n"),
 (ptrdiff_t)(name_ptr-name_dir),(long)max_names);
@@ -1992,5 +1992,5 @@ printf(_("%td tokens (out of %ld)\n"),
 (ptrdiff_t)(tok_ptr-tok_mem),(long)max_toks);
 }
 
-#line 362 "cwebdir/ctang-w2c.ch"
+#line 364 "cwebdir/ctang-w2c.ch"
 /*:103*/
diff --git a/Build/source/texk/web2c/cwebdir/ChangeLog b/Build/source/texk/web2c/cwebdir/ChangeLog
index c370c7d0621..3e55aa657b8 100644
--- a/Build/source/texk/web2c/cwebdir/ChangeLog
+++ b/Build/source/texk/web2c/cwebdir/ChangeLog
@@ -1,3 +1,14 @@
+2022-03-10  Andreas Scherer  <https://ascherer.github.io>
+
+	* Makefile,
+	* ctang-w2c.ch,
+	* ctangle.c,
+	* ctangle.w,
+	* ctwill-mini.ch,
+	* ctwill-w2c.ch,
+	* cweav-w2c.ch,
+	* cweave.w: Make 'fall thru' comments active.
+
 2022-02-18  Andreas Scherer  <https://ascherer.github.io>
 
 	* common.c,
diff --git a/Build/source/texk/web2c/cwebdir/Makefile b/Build/source/texk/web2c/cwebdir/Makefile
index 92e59b857b8..d3bc422059b 100644
--- a/Build/source/texk/web2c/cwebdir/Makefile
+++ b/Build/source/texk/web2c/cwebdir/Makefile
@@ -50,7 +50,7 @@ TCHANGES=
 WCHANGES=
 
 # We keep debugging info around, for fun, but most users don't need it
-CFLAGS = -g
+CFLAGS = -g # -Wall -Wextra -Wimplicit-fallthrough=2 # check compiler warnings
 #CFLAGS = -O
 LINKFLAGS = -g
 #LINKFLAGS = -s # for smaller (stripped) executables on many UNIX systems
diff --git a/Build/source/texk/web2c/cwebdir/ctang-w2c.ch b/Build/source/texk/web2c/cwebdir/ctang-w2c.ch
index 6a284181224..ed91b9d7e5d 100644
--- a/Build/source/texk/web2c/cwebdir/ctang-w2c.ch
+++ b/Build/source/texk/web2c/cwebdir/ctang-w2c.ch
@@ -319,8 +319,10 @@ case output_defs_code: if (t!=section_name) err_print(_("! Misplaced @@h"));
 @z
 
 @x
+          } @=/* otherwise fall through */@>
         default: err_print("! Double @@ should be used in limbo");
 @y
+          } @=/* otherwise fall through */@>
         default: err_print(_("! Double @@ should be used in limbo"));
 @z
 
diff --git a/Build/source/texk/web2c/cwebdir/ctangle.c b/Build/source/texk/web2c/cwebdir/ctangle.c
index b6037a87dd9..bc00c0cf7f3 100644
--- a/Build/source/texk/web2c/cwebdir/ctangle.c
+++ b/Build/source/texk/web2c/cwebdir/ctangle.c
@@ -866,7 +866,7 @@ case string:if(out_state==verbatim)out_state= normal;
 else out_state= verbatim;break;
 case'/':C_putc('/');out_state= post_slash;break;
 case'*':if(out_state==post_slash)C_putc(' ');
-
+/* fall through */
 default:C_putc(cur_char);out_state= normal;break;
 }
 }
@@ -1627,7 +1627,7 @@ if(*(loc-1)!='>')
 err_print("! Double @ should be used in control text");
 
 break;
-}
+}/* otherwise fall through */
 default:err_print("! Double @ should be used in limbo");
 
 }
diff --git a/Build/source/texk/web2c/cwebdir/ctangle.w b/Build/source/texk/web2c/cwebdir/ctangle.w
index c2fc88af747..a0f7cc17d4a 100644
--- a/Build/source/texk/web2c/cwebdir/ctangle.w
+++ b/Build/source/texk/web2c/cwebdir/ctangle.w
@@ -666,7 +666,7 @@ restart:
         else out_state=verbatim; break;
       case '/': C_putc('/'); out_state=post_slash; break;
       case '*': if (out_state==post_slash) C_putc(' ');
-        /* fall through */
+        @=/* fall through */@>
       default: C_putc(cur_char); out_state=normal; break;
     }
 }
@@ -1510,7 +1510,7 @@ skip_limbo(void)
             err_print("! Double @@ should be used in control text");
 @.Double @@ should be used...@>
           break;
-          } /* otherwise fall through */
+          } @=/* otherwise fall through */@>
         default: err_print("! Double @@ should be used in limbo");
 @.Double @@ should be used...@>
       }
diff --git a/Build/source/texk/web2c/cwebdir/ctwill-mini.ch b/Build/source/texk/web2c/cwebdir/ctwill-mini.ch
index e7725904503..0411aad1d06 100644
--- a/Build/source/texk/web2c/cwebdir/ctwill-mini.ch
+++ b/Build/source/texk/web2c/cwebdir/ctwill-mini.ch
@@ -1556,7 +1556,7 @@ Section 233--234.
       case end_translation: return;
       case identifier: case res_word: @<Output an identifier@>@; break;
       case section_code: @<Output a section name@>@; break;
-      case math_rel: out_str("\\MRL{"@q}@>); /* fall through */
+      case math_rel: out_str("\\MRL{"@q}@>); @=/* fall through */@>
 @.\\MRL@>
       case noop: case inserted: break;
       case cancel: case big_cancel: c=0; b=a;
@@ -1578,11 +1578,11 @@ Section 233--234.
         if (a!=big_force) {
           out_str("\\1\\1"); goto reswitch;
         }
-        else dindent_pending=true; /* fall through */
+        else dindent_pending=true; @=/* fall through */@>
       case indent: case outdent: case opt: case backup: case break_space:
       case force: case big_force: case preproc_line: @<Output a control,
         look ahead in case of line breaks, possibly |goto reswitch|@>@; break;
-      case quoted_char: out(*(cur_tok++)); /* fall through */
+      case quoted_char: out(*(cur_tok++)); @=/* fall through */@>
       case qualifier: break;
       default: out(a); /* otherwise |a| is an ordinary character */
     }
@@ -1598,7 +1598,7 @@ Section 233--234.
       case end_translation: return;
       case identifier: case res_word: @<Output an identifier@>@; break;
       case section_code: @<Output a section name@>@; break;
-      case math_rel: out_str("\\MRL{"@q}@>); /* fall through */
+      case math_rel: out_str("\\MRL{"@q}@>); @=/* fall through */@>
 @.\\MRL@>
       case noop: case inserted: break;
       case cancel: case big_cancel: c=0; b=a;
@@ -1620,11 +1620,11 @@ Section 233--234.
         if (a!=big_force) {
           out_str("\\1\\1"); goto reswitch;
         }
-        else dindent_pending=true; /* fall through */
+        else dindent_pending=true; @=/* fall through */@>
       case indent: case outdent: case opt: case backup: case break_space:
       case force: case big_force: case preproc_line: @<Output a control,
         look ahead in case of line breaks, possibly |goto reswitch|@>@; break;
-      case quoted_char: out(*(cur_tok++)); /* fall through */
+      case quoted_char: out(*(cur_tok++)); @=/* fall through */@>
       case qualifier: break;
       default: out(a); /* otherwise |a| is an ordinary character */
     }
@@ -1673,12 +1673,12 @@ Section 240.
 @x
     case ' ': case '\\': case '#': case '%': case '$': case '^':
     case '{': case '}': case '~': case '&': case '_':
-      out('\\'); /* falls through */
+      out('\\'); @=/* falls through */@>
 @y
     case ' ': case '\\': case '#': case '%': @/
     case '$': case '^': case '{': case '}': @/
     case '~': case '&': case '_': @/
-      out('\\'); /* falls through */
+      out('\\'); @=/* falls through */@>
 @z
 
 Section 242.
diff --git a/Build/source/texk/web2c/cwebdir/ctwill-w2c.ch b/Build/source/texk/web2c/cwebdir/ctwill-w2c.ch
index 8b0ec0f7606..1a8da3c0b80 100644
--- a/Build/source/texk/web2c/cwebdir/ctwill-w2c.ch
+++ b/Build/source/texk/web2c/cwebdir/ctwill-w2c.ch
@@ -1099,8 +1099,10 @@ flush_buffer(out_ptr,false,false);
 @z
 
 @x
+        } @=/* otherwise fall through */@>
       default: err_print("! Improper macro definition"); break;
 @y
+        } @=/* otherwise fall through */@>
       default: err_print(_("! Improper macro definition")); break;
 @z
 
diff --git a/Build/source/texk/web2c/cwebdir/cweav-w2c.ch b/Build/source/texk/web2c/cwebdir/cweav-w2c.ch
index 80951343d37..2d9a5c24360 100644
--- a/Build/source/texk/web2c/cwebdir/cweav-w2c.ch
+++ b/Build/source/texk/web2c/cwebdir/cweav-w2c.ch
@@ -523,8 +523,10 @@ if (show_progress) fputs(_("\nWriting the output file..."),stdout);
 @z
 
 @x
+        } @=/* otherwise fall through */@>
       default: err_print("! Improper macro definition"); break;
 @y
+        } @=/* otherwise fall through */@>
       default: err_print(_("! Improper macro definition")); break;
 @z
 
diff --git a/Build/source/texk/web2c/cwebdir/cweave.w b/Build/source/texk/web2c/cwebdir/cweave.w
index 5db1c371b55..501528d4fe4 100644
--- a/Build/source/texk/web2c/cwebdir/cweave.w
+++ b/Build/source/texk/web2c/cwebdir/cweave.w
@@ -948,7 +948,7 @@ switch(ccode[c=*loc++]) {
   case verbatim: @<Scan a verbatim string@>@;
   case ord: @<Get a string@>@;
   case xref_roman: case xref_wildcard: case xref_typewriter: case noop:
-  case TeX_string: skip_restricted(); /* fall through */
+  case TeX_string: skip_restricted(); @=/* fall through */@>
   default: return ccode[c];
 }
 
@@ -2535,10 +2535,12 @@ text_pointer p)
         if (name_dir[r].ilk==case_like) return case_found;
         if (name_dir[r].ilk==operator_like) return operator_found;
         if (name_dir[r].ilk!=raw_int) break;
+        @=/* else fall through */@>
       case 1: return j;
       case 4: case 5: /* |tok_flag| or |inner_tok_flag| */
         if ((q=find_first_ident(tok_start+r))!=no_ident_found)
           return q;
+        @=/* else fall through */@>
       default: ; /* char, |section_flag|, fall thru: move on to next token */
         if (*j==inserted) return no_ident_found; /* ignore inserts */
         else if (*j==qualifier) j++; /* bypass namespace qualifier */
@@ -3919,7 +3921,7 @@ make_output(void) /* outputs the equivalents of tokens */
       case end_translation: return;
       case identifier: case res_word: @<Output an identifier@>@; break;
       case section_code: @<Output a section name@>@; break;
-      case math_rel: out_str("\\MRL{"@q}@>); /* fall through */
+      case math_rel: out_str("\\MRL{"@q}@>); @=/* fall through */@>
 @.\\MRL@>
       case noop: case inserted: break;
       case cancel: case big_cancel: c=0; b=a;
@@ -3941,11 +3943,11 @@ make_output(void) /* outputs the equivalents of tokens */
         if (a!=big_force) {
           out_str("\\1\\1"); goto reswitch;
         }
-        else dindent_pending=true; /* fall through */
+        else dindent_pending=true; @=/* fall through */@>
       case indent: case outdent: case opt: case backup: case break_space:
       case force: case big_force: case preproc_line: @<Output a control,
         look ahead in case of line breaks, possibly |goto reswitch|@>@; break;
-      case quoted_char: out(*(cur_tok++)); /* fall through */
+      case quoted_char: out(*(cur_tok++)); @=/* fall through */@>
       case qualifier: break;
       default: out(a); /* otherwise |a| is an ordinary character */
     }
@@ -4100,7 +4102,7 @@ while (k<k_limit) {
     switch (b) {
     case ' ': case '\\': case '#': case '%': case '$': case '^':
     case '{': case '}': case '~': case '&': case '_':
-      out('\\'); /* falls through */
+      out('\\'); @=/* falls through */@>
 @.\\\ @>
 @.\\\\@>
 @.\\\#@>
@@ -4353,7 +4355,7 @@ it starts after we scan the matching `\.)'.
         app_scrap(raw_int,no_math);
         if ((next_control=get_next())==')') {
           app(next_control); next_control=get_next(); break;
-        } /* otherwise fall through */
+        } @=/* otherwise fall through */@>
       default: err_print("! Improper macro definition"); break;
       }
       app('$');
@@ -4786,6 +4788,7 @@ lowcase: out_str("\\\\");
   case wildcard: out_str("\\9");@+ goto not_an_identifier;
 @.\\9@>
   case typewriter: out_str("\\.");
+  @=/* fall through */@>
 @.\\.@>
   case roman: not_an_identifier: out_name(cur_name,false); goto name_done;
   case custom: