invoke.texi (-Wimplicit-fallthrough): Document FALLTHRU comment style changes.

* doc/invoke.texi (-Wimplicit-fallthrough): Document FALLTHRU comment
	style changes.

	* lex.c (fallthrough_comment_p): Extend to handle more common FALLTHRU
	comment styles.

	* c-c++-common/Wimplicit-fallthrough-23.c (foo): Add further tests.

From-SVN: r240885

gcc/ChangeLog

@@ -1,5 +1,8 @@
 2016-10-08  Jakub Jelinek  <jakub@redhat.com>
 
+	* doc/invoke.texi (-Wimplicit-fallthrough): Document FALLTHRU comment
+	style changes.
+
 	* doc/invoke.texi (-Wimplicit-fallthrough): Document the accepted
 	FALLTHRU comment styles.
 

gcc/doc/invoke.texi

@@ -4179,11 +4179,13 @@ should match one of the following regular expressions:
 
 @item @code{@@fallthrough@@}
 
-@item @code{[ \t]*FALL(S | |-)?THR(OUGH|U)\.?[ \t]*}
+@item @code{lint -fallthrough ?}
 
-@item @code{[ \t]*Fall((s | |-)[Tt]|t)hr(ough|u)\.?[ \t]*}
+@item @code{[ \t.!]*(ELSE |INTENTIONAL(LY)? )?FALL(S | |-)?THR(OUGH|U)[ \t.!]*(-[^\n\r]*)?}
 
-@item @code{[ \t]*fall(s | |-)?thr(ough|u)\.?[ \t]*}
+@item @code{[ \t.!]*(Else |Intentional(ly)? )?Fall((s | |-)[Tt]|t)hr(ough|u)[ \t.!]*(-[^\n\r]*)?}
+
+@item @code{[ \t.!]*([Ee]lse |[Ii]ntentional(ly)? )?fall(s | |-)?thr(ough|u)[ \t.!]*(-[^\n\r]*)?}
 
 @end itemize
 

gcc/testsuite/ChangeLog

@@ -1,5 +1,7 @@
 2016-10-08  Jakub Jelinek  <jakub@redhat.com>
 
+	* c-c++-common/Wimplicit-fallthrough-23.c (foo): Add further tests.
+
 	* c-c++-common/Wimplicit-fallthrough-23.c: New test.
 	* c-c++-common/Wimplicit-fallthrough-24.c: New test.
 

gcc/testsuite/c-c++-common/Wimplicit-fallthrough-23.c

@@ -21,15 +21,39 @@ foo (int i)
     case 4:
       bar (4);
       break;
+    case 5:
+      bar (5);			/* { dg-bogus "this statement may \[laf]* through" } */
+      /* Else Fall-Thru!  */
+    case 6:
+      bar (6);
+      break;
     case 7:
       bar (7);			/* { dg-bogus "this statement may \[laf]* through" } */
       /* Some comment.  */
-      /* fallthrough.  */
+      /* ... fallthrough ...  */
       /* Some other comment.  */
       /* And yet another.  */
     case 8:
       bar (8);
       break;
+    case 9:
+      bar (9);			/* { dg-bogus "this statement may \[laf]* through" } */
+      /* Intentional Fallthru */
+    case 10:
+      bar (10);
+      break;
+    case 11:
+      bar (11);			/* { dg-bogus "this statement may \[laf]* through" } */
+      /* intentionally fall through  */
+    case 12:
+      bar (12);
+      break;
+    case 13:
+      bar (13);			/* { dg-bogus "this statement may \[laf]* through" } */
+      /* Falls Through - for reasons known only to the author.  */
+    case 14:
+      bar (14);
+      break;
     case 15:
       bar (15);			/* { dg-bogus "this statement may \[laf]* through" } */
       /*-fallthrough*/
@@ -42,12 +66,42 @@ foo (int i)
     case 18:
       bar (18);
       break;
+    case 19:
+      bar (19);			/* { dg-bogus "this statement may \[laf]* through" } */
+      /*lint -fallthrough*/
+    case 20:
+      bar (20);
+      break;
+    case 21:
+      bar (21);			/* { dg-bogus "this statement may \[laf]* through" } */
+      /*lint -fallthrough */
+    case 22:
+      bar (22);
+      break;
     case 23:
       bar (23);			/* { dg-bogus "this statement may \[laf]* through" } */
       /*fallthru*/
     case 24:
       bar (24);
       break;
+    case 25:
+      bar (25);			/* { dg-bogus "this statement may \[laf]* through" } */
+      /*Else fallthru*/
+    case 26:
+      bar (26);
+      break;
+    case 27:
+      bar (27);			/* { dg-bogus "this statement may \[laf]* through" } */
+      /*Intentional fallthru*/
+    case 28:
+      bar (28);
+      break;
+    case 29:
+      bar (29);			/* { dg-bogus "this statement may \[laf]* through" } */
+      /*Intentionally fallthru*/
+    case 30:
+      bar (30);
+      break;
     case 31:
       bar (31);			/* { dg-bogus "this statement may \[laf]* through" } */
       /*Falls thru*/
@@ -78,15 +132,39 @@ foo (int i)
     case 4:
       bar (4);
       break;
+    case 5:
+      bar (5);			/* { dg-bogus "this statement may \[laf]* through" } */
+      // Else Fall-Thru!
+    case 6:
+      bar (6);
+      break;
     case 7:
       bar (7);			/* { dg-bogus "this statement may \[laf]* through" } */
       // Some comment.
-      // fallthrough
+      // ... fallthrough ...
       // Some other comment.
       // And yet another.
     case 8:
       bar (8);
       break;
+    case 9:
+      bar (9);			/* { dg-bogus "this statement may \[laf]* through" } */
+      // Intentional Fallthru
+    case 10:
+      bar (10);
+      break;
+    case 11:
+      bar (11);			/* { dg-bogus "this statement may \[laf]* through" } */
+      // intentionally fall through 
+    case 12:
+      bar (12);
+      break;
+    case 13:
+      bar (13);			/* { dg-bogus "this statement may \[laf]* through" } */
+      // Falls Through - for reasons known only to the author.
+    case 14:
+      bar (14);
+      break;
     case 15:
       bar (15);			/* { dg-bogus "this statement may \[laf]* through" } */
       //-fallthrough
@@ -99,12 +177,42 @@ foo (int i)
     case 18:
       bar (18);
       break;
+    case 19:
+      bar (19);			/* { dg-bogus "this statement may \[laf]* through" } */
+      //lint -fallthrough
+    case 20:
+      bar (20);
+      break;
+    case 21:
+      bar (21);			/* { dg-bogus "this statement may \[laf]* through" } */
+      //lint -fallthrough 
+    case 22:
+      bar (22);
+      break;
     case 23:
       bar (23);			/* { dg-bogus "this statement may \[laf]* through" } */
       //fallthru
     case 24:
       bar (24);
       break;
+    case 25:
+      bar (25);			/* { dg-bogus "this statement may \[laf]* through" } */
+      //Else fallthru
+    case 26:
+      bar (26);
+      break;
+    case 27:
+      bar (27);			/* { dg-bogus "this statement may \[laf]* through" } */
+      //Intentional fallthru
+    case 28:
+      bar (28);
+      break;
+    case 29:
+      bar (29);			/* { dg-bogus "this statement may \[laf]* through" } */
+      //Intentionally fallthru
+    case 30:
+      bar (30);
+      break;
     case 31:
       bar (31);			/* { dg-bogus "this statement may \[laf]* through" } */
       //Falls thru

libcpp/ChangeLog

@@ -1,5 +1,8 @@
 2016-10-08  Jakub Jelinek  <jakub@redhat.com>
 
+	* lex.c (fallthrough_comment_p): Extend to handle more common FALLTHRU
+	comment styles.
+
 	* lex.c (fallthrough_comment_p): Fix off-by-one size comparison
 	errors, cleanup.
 	(_cpp_lex_direct): Allow arbitrary comments in between

libcpp/lex.c

@@ -2060,22 +2060,86 @@ fallthrough_comment_p (cpp_reader *pfile, const unsigned char *comment_start)
       from += 1 + len;
     }
   /* Whole comment contents (regex):
-     [ \t]*FALL(S | |-)?THR(OUGH|U)\.?[ \t]*
+     lint -fallthrough ?
-     [ \t]*Fall((s | |-)[Tt]|t)hr(ough|u)\.?[ \t]*
+   */
-     [ \t]*fall(s | |-)?thr(ough|u)\.?[ \t]*
+  else if (*from == 'l')
+    {
+      size_t len = sizeof "int -fallthrough" - 1;
+      if ((size_t) (pfile->buffer->cur - from - 1) < len)
+	return false;
+      if (memcmp (from + 1, "int -fallthrough", len))
+        return false;
+      from += 1 + len;
+      if (*from == ' ')
+        from++;
+    }
+  /* Whole comment contents (regex):
+     [ \t.!]*(ELSE |INTENTIONAL(LY)? )?FALL(S | |-)?THR(OUGH|U)[ \t.!]*(-[^\n\r]*)?
+     [ \t.!]*(Else |Intentional(ly)? )?Fall((s | |-)[Tt]|t)hr(ough|u)[ \t.!]*(-[^\n\r]*)?
+     [ \t.!]*([Ee]lse |[Ii]ntentional(ly)? )?fall(s | |-)?thr(ough|u)[ \t.!]*(-[^\n\r]*)?
    */
   else
     {
-      while (*from == ' ' || *from == '\t')
+      while (*from == ' ' || *from == '\t' || *from == '.' || *from == '!')
 	from++;
       unsigned char f = *from;
+      bool all_upper = false;
+      if (f == 'E' || f == 'e')
+        {
+          if ((size_t) (pfile->buffer->cur - from)
+	      < sizeof "else fallthru" - 1)
+	    return false;
+	  if (f == 'E' && memcmp (from + 1, "LSE F", sizeof "LSE F" - 1) == 0)
+	    all_upper = true;
+	  else if (memcmp (from + 1, "lse ", sizeof "lse " - 1))
+	    return false;
+	  from += sizeof "else " - 1;
+	  if (f == 'e' && *from == 'F')
+	    return false;
+	  f = *from;
+        }
+      else if (f == 'I' || f == 'i')
+        {
+          if ((size_t) (pfile->buffer->cur - from)
+	      < sizeof "intentional fallthru" - 1)
+	    return false;
+	  if (f == 'I' && memcmp (from + 1, "NTENTIONAL",
+				  sizeof "NTENTIONAL" - 1) == 0)
+	    all_upper = true;
+	  else if (memcmp (from + 1, "ntentional",
+			   sizeof "ntentional" - 1))
+	    return false;
+	  from += sizeof "intentional" - 1;
+	  if (*from == ' ')
+	    {
+	      from++;
+	      if (all_upper && *from == 'f')
+		return false;
+	    }
+	  else if (all_upper)
+	    {
+	      if (memcmp (from, "LY F", sizeof "LY F" - 1))
+		return false;
+	      from += sizeof "LY " - 1;
+	    }
+	  else
+	    {
+	      if (memcmp (from, "ly ", sizeof "ly " - 1))
+		return false;
+	      from += sizeof "ly " - 1;
+	    }
+	  if (f == 'i' && *from == 'F')
+	    return false;
+	  f = *from;
+        }
       if (f != 'F' && f != 'f')
 	return false;
       if ((size_t) (pfile->buffer->cur - from) < sizeof "fallthru" - 1)
 	return false;
-      bool all_upper = false;
       if (f == 'F' && memcmp (from + 1, "ALL", sizeof "ALL" - 1) == 0)
 	all_upper = true;
+      else if (all_upper)
+	return false;
       else if (memcmp (from + 1, "all", sizeof "all" - 1))
 	return false;
       from += sizeof "fall" - 1;
@@ -2100,10 +2164,28 @@ fallthrough_comment_p (cpp_reader *pfile, const unsigned char *comment_start)
 	}
       else
 	from += sizeof "thru" - 1;
-      if (*from == '.')
+      while (*from == ' ' || *from == '\t' || *from == '.' || *from == '!')
-	from++;
-      while (*from == ' ' || *from == '\t')
 	from++;
+      if (*from == '-')
+	{
+	  from++;
+	  if (*comment_start == '*')
+	    {
+	      do
+		{
+		  while (*from && *from != '*'
+			 && *from != '\n' && *from != '\r')
+		    from++;
+		  if (*from != '*' || from[1] == '/')
+		    break;
+		  from++;
+		}
+	      while (1);
+	    }
+	  else
+	    while (*from && *from != '\n' && *from != '\r')
+	      from++;
+	}
     }
   /* C block comment.  */
   if (*comment_start == '*')