Re: [patch, fortran] PR39229 No warning of truncated lines if a continuation line follows

[Jerry DeLisle <jvdelisle at verizon dot net>]

Jerry DeLisle wrote:

> Regarding the test case.  You may notice that since line 10 is continued 
> to line  11, next_statement does not see the truncation of line 11 
> because on its next call, it has moved on to line 12.  This means that 
> this patch is a vast improvement but not ideal.  I would like to get 
> this much in for now and will leave the PR open for now while I study 
> the situation some more.
I found some more time to work on this.  The attached patch is simplified from 
the previous and I believe takes care of all the cases.

Regression tested on x86-64. Two test cases, one for free-form and one for 
fixed-form.

OK to commit?

Regards,

Jerry

2009-08-29  Jerry DeLisle  <jvdelisle@gcc.gnu.org>

	PR fortran/39229
	* scanner.c (next_char): Fix typo in comment.
	(gfc_get_char_literal): Warn if truncate flag is set for both fixed and
	free form source, adjusting error locus as needed.
	* parse.c (next_fixed): Clear the truncate flag.
	(next_statement): Remove truncate warning.

Index: scanner.c
===================================================================
--- scanner.c	(revision 151156)
+++ scanner.c	(working copy)
@@ -614,7 +614,7 @@ next_char (void)
 
 /* Skip a comment.  When we come here the parse pointer is positioned
    immediately after the comment character.  If we ever implement
-   compiler directives withing comments, here is where we parse the
+   compiler directives within comments, here is where we parse the
    directive.  */
 
 static void
@@ -1080,6 +1080,17 @@ restart:
 	    }
 	}
 
+      /* Check to see if the continuation line was truncated.  */
+      if (gfc_option.warn_line_truncation && gfc_current_locus.lb != NULL
+	  && gfc_current_locus.lb->truncated)
+	{
+	  int maxlen = gfc_option.free_line_length;
+	  gfc_current_locus.lb->truncated = 0;
+	  gfc_current_locus.nextc += maxlen;
+	  gfc_warning_now ("Line truncated at %L", &gfc_current_locus);
+	  gfc_current_locus.nextc -= maxlen;
+	}
+
       /* Now find where it continues. First eat any comment lines.  */
       openmp_cond_flag = skip_free_comments ();
 
@@ -1158,6 +1169,14 @@ restart:
       if (c != '\n')
 	goto done;
 
+      /* Check to see if the continuation line was truncated.  */
+      if (gfc_option.warn_line_truncation && gfc_current_locus.lb != NULL
+	  && gfc_current_locus.lb->truncated)
+	{
+	  gfc_current_locus.lb->truncated = 0;
+	  gfc_warning_now ("Line truncated at %L", &gfc_current_locus);
+	}
+
       prev_openmp_flag = openmp_flag;
       continue_flag = 1;
       old_loc = gfc_current_locus;
Index: parse.c
===================================================================
--- parse.c	(revision 151156)
+++ parse.c	(working copy)
@@ -849,6 +849,8 @@ next_fixed (void)
 blank_line:
   if (digit_flag)
     gfc_warning ("Ignoring statement label in empty statement at %C");
+    
+  gfc_current_locus.lb->truncated = 0;
   gfc_advance_line ();
   return ST_NONE;
 }
@@ -862,6 +864,7 @@ next_statement (void)
 {
   gfc_statement st;
   locus old_locus;
+
   gfc_new_block = NULL;
 
   gfc_current_ns->old_cl_list = gfc_current_ns->cl_list;
@@ -871,15 +874,8 @@ next_statement (void)
       gfc_buffer_error (1);
 
       if (gfc_at_eol ())
-	{
-	  if ((gfc_option.warn_line_truncation || gfc_current_form == FORM_FREE)
-	      && gfc_current_locus.lb
-	      && gfc_current_locus.lb->truncated)
-	    gfc_warning_now ("Line truncated at %C");
+	gfc_advance_line ();
 
-	  gfc_advance_line ();
-	}
-
       gfc_skip_comments ();
 
       if (gfc_at_end ())

! { dg-do compile }
! { dg-options "-std=gnu -ffixed-form -Wline-truncation" }
! PR39229 No warning of truncated lines if a continuation line follows 
      ! expected: no warning by default (as column 73+ is often used for )
      ! comments in fixed-form source code.
      ! however, with -wline-truncation there shall be a warning.
      implicit none
        call foo([11, 22, 33, 44, 55, 66, 770, 9900, 1100, 1100, 120], 12 warn
     &          , 'hello')
      print *, min(35 
     1                                        ,                        25 warn
     2  )
      contains
      subroutine foo(a,n,s)
        integer :: a(*), n, i
        character(len=*) :: s
        do i = 1, n
          print *, s, a(i)
        end do
      end subroutine foo
      end
! { dg-warning "Line truncated" " " { target *-*-* } 8 }
! { dg-warning "Line truncated" " " { target *-*-* } 11 }

! { dg-do compile }
! { dg-options "-Wline-truncation -ffree-line-length-80" }
! PR39229 No warning of truncated lines if a continuation line follows 
  implicit none
  call foo([11, 22, 33, 44, 55, 66, 770, 9900, 1100, 1100, 120],11,'hello') !no warn

  print *, min(35 &
   &  ,                        25  ), " Explanation ! "                         warn
  contains
   subroutine foo(a,n,s)
     integer :: a(*), n, i
     character(len=*) :: s
     do i = 1, n
       print *, s, a(i)
     end do
   end subroutine foo
  end
! { dg-warning "Line truncated" " " { target *-*-* } 8 }