Re: [gfortran, patch] fix runtime out-of-bounds checking

[Steve Kargl <sgk at troutmask dot apl dot washington dot edu>]

On Wed, Jun 07, 2006 at 05:43:39PM +0200, Fran?ois-Xavier Coudert wrote:
> :ADDPATCH fortran:
> 
> Today, as part of my bounds-checking series, here is a patch that
> fixes runtime bounds-checking. Currently, the front-end generates
> errors for valid code (for example, for zero-sized sections), which
> this patch corrects. I also added a check for zero-stride, and checks
> for the last element of sections. I also fixed the text of the
> messages, from "bounds mismatch" to "Array reference out of bounds".
> 
> In fact, this patch generates code for the same checks than my
> previous patch for compile-time checks did.
> 
> Bootstrapped and regtested on i686-linux, tested that it didn't
> introduce regressions for the testcase run with -fbounds-check. I also
> manually checked that runtime errors are obtained on all the erroneous
> statements of my compile-time testcase
> (http://gcc.gnu.org/ml/fortran/2006-06/msg00071.html).
> 
> OK for mainline and 4.1?
> 

OK with minor changes.

Index: trans-array.c
===================================================================
--- trans-array.c	(revision 114461)
+++ trans-array.c	(working copy)
 
-	      /* Check lower bound.  */
-	      bound = gfc_conv_array_lbound (desc, dim);
-	      tmp = info->start[n];
-	      tmp = fold_build2 (LT_EXPR, boolean_type_node, tmp, bound);
+	      /* This is the run-time equivalent of resolve.c's
+	         check_dimension().  The logical is more readable there
+	         that it is here, with all the trees.  */

s/that/than

+	      /* Compute the last element of the range, which is not
+	         necessarily "end" (think 0:5:3, which doesn't contain 5)
+		 and check it against both lower and upper bounds.  */

In my mailer the above comment appears malformed.  Can you check it?

-- 
Steve