diff mbox series

[fortran] Updated fix PR 92961, ICE on division by zero error in array bounds

Message ID 262fe23c-f23f-ede0-40bd-478696131a69@netcologne.de
State New
Headers show
Series [fortran] Updated fix PR 92961, ICE on division by zero error in array bounds | expand

Commit Message

Thomas Koenig Dec. 22, 2019, 3:28 p.m. UTC 
Hello world,

here is an update for the fix for PR 92961, which also takes care
of the second test case in the PR (included in the first one).

The patch itself should be clear enough - make sure that there
is a MATCH_ERROR on matching an array spec which contains 0/(0).
Rather than pass around information several calls deep, I chose
to use a global variable.

Regression-tested. OK for trunk?

(Only a few bugs to fix to be at least below 900 bugs at the end
of the year, by the way - we are at 389 submitted bugs vs. 461 closed,
which is not bad).

Regards

	Thomas

2019-12-22  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/92961
	* gfortran.h (gfc_seen_div0): Add declaration.
	* arith.h (gfc_seen_div0): Add definition.
	(eval_intrinsic): For integer division by zero, set gfc_seen_div0.
	* decl.c (variable_decl):  If resolution resp. simplification
	fails for array spec and a division of zero error has been
	seen, return MATCH_ERROR.

2019-12-22  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/92961
	* gfortran.dg/arith_divide_2.f90: New test.

Comments

Thomas Koenig Dec. 29, 2019, 10:15 a.m. UTC | #1 
Am 22.12.19 um 16:28 schrieb Thomas Koenig:

> here is an update for the fix for PR 92961, which also takes care
> of the second test case in the PR (included in the first one).
> 
> The patch itself should be clear enough - make sure that there
> is a MATCH_ERROR on matching an array spec which contains 0/(0).
> Rather than pass around information several calls deep, I chose
> to use a global variable.
> 
> Regression-tested. OK for trunk?

Ping?

I'd like to get the bug count at least go to 902 in the old year
(if 900 cannot be achieved :-)

Regards

	Thomas
Jerry DeLisle Dec. 30, 2019, 2:51 a.m. UTC | #2 
This one looks OK Thomas

Cheers,

Jerry

On 12/22/19 7:28 AM, Thomas Koenig wrote:
> Hello world,
> 
> here is an update for the fix for PR 92961, which also takes care
> of the second test case in the PR (included in the first one).
> 
> The patch itself should be clear enough - make sure that there
> is a MATCH_ERROR on matching an array spec which contains 0/(0).
> Rather than pass around information several calls deep, I chose
> to use a global variable.
> 
> Regression-tested. OK for trunk?
> 
> (Only a few bugs to fix to be at least below 900 bugs at the end
> of the year, by the way - we are at 389 submitted bugs vs. 461 closed,
> which is not bad).
> 
> Regards
> 
>      Thomas
> 
> 2019-12-22  Thomas Koenig  <tkoenig@gcc.gnu.org>
> 
>      PR fortran/92961
>      * gfortran.h (gfc_seen_div0): Add declaration.
>      * arith.h (gfc_seen_div0): Add definition.
>      (eval_intrinsic): For integer division by zero, set gfc_seen_div0.
>      * decl.c (variable_decl):  If resolution resp. simplification
>      fails for array spec and a division of zero error has been
>      seen, return MATCH_ERROR.
> 
> 2019-12-22  Thomas Koenig  <tkoenig@gcc.gnu.org>
> 
>      PR fortran/92961
>      * gfortran.dg/arith_divide_2.f90: New test.
diff mbox series

Patch

Index: gfortran.h
===================================================================
--- gfortran.h	(Revision 279639)
+++ gfortran.h	(Arbeitskopie)
@@ -2995,6 +2995,8 @@  void gfc_arith_done_1 (void);
 arith gfc_check_integer_range (mpz_t p, int kind);
 bool gfc_check_character_range (gfc_char_t, int);
 
+extern bool gfc_seen_div0;
+
 /* trans-types.c */
 bool gfc_check_any_c_kind (gfc_typespec *);
 int gfc_validate_kind (bt, int, bool);
Index: arith.c
===================================================================
--- arith.c	(Revision 279639)
+++ arith.c	(Arbeitskopie)
@@ -32,6 +32,8 @@  along with GCC; see the file COPYING3.  If not see
 #include "target-memory.h"
 #include "constructor.h"
 
+bool gfc_seen_div0;
+
 /* MPFR does not have a direct replacement for mpz_set_f() from GMP.
    It's easily implemented with a few calls though.  */
 
@@ -1620,6 +1622,10 @@  eval_intrinsic (gfc_intrinsic_op op,
       gfc_error (gfc_arith_error (rc), &op1->where);
       if (rc == ARITH_OVERFLOW)
 	goto done;
+
+      if (rc == ARITH_DIV0 && op2->ts.type == BT_INTEGER)
+	gfc_seen_div0 = true;
+
       return NULL;
     }
 
Index: decl.c
===================================================================
--- decl.c	(Revision 279639)
+++ decl.c	(Arbeitskopie)
@@ -2551,7 +2551,12 @@  variable_decl (int elem)
 	  for (int i = 0; i < as->rank; i++)
 	    {
 	      e = gfc_copy_expr (as->lower[i]);
-	      gfc_resolve_expr (e);
+	      if (!gfc_resolve_expr (e) && gfc_seen_div0)
+		{
+		  m = MATCH_ERROR;
+		  goto cleanup;
+		}
+
 	      gfc_simplify_expr (e, 0);
 	      if (e && (e->expr_type != EXPR_CONSTANT))
 		{
@@ -2561,7 +2566,12 @@  variable_decl (int elem)
 	      gfc_free_expr (e);
 
 	      e = gfc_copy_expr (as->upper[i]);
-	      gfc_resolve_expr (e);
+	      if (!gfc_resolve_expr (e)  && gfc_seen_div0)
+		{
+		  m = MATCH_ERROR;
+		  goto cleanup;
+		}
+
 	      gfc_simplify_expr (e, 0);
 	      if (e && (e->expr_type != EXPR_CONSTANT))
 		{
@@ -2587,7 +2597,12 @@  variable_decl (int elem)
 	      if (e->expr_type != EXPR_CONSTANT)
 		{
 		  n = gfc_copy_expr (e);
-		  gfc_simplify_expr (n, 1);
+		  if (!gfc_simplify_expr (n, 1)  && gfc_seen_div0) 
+		    {
+		      m = MATCH_ERROR;
+		      goto cleanup;
+		    }
+
 		  if (n->expr_type == EXPR_CONSTANT)
 		    gfc_replace_expr (e, n);
 		  else
@@ -2597,7 +2612,12 @@  variable_decl (int elem)
 	      if (e->expr_type != EXPR_CONSTANT)
 		{
 		  n = gfc_copy_expr (e);
-		  gfc_simplify_expr (n, 1);
+		  if (!gfc_simplify_expr (n, 1)  && gfc_seen_div0) 
+		    {
+		      m = MATCH_ERROR;
+		      goto cleanup;
+		    }
+		  
 		  if (n->expr_type == EXPR_CONSTANT)
 		    gfc_replace_expr (e, n);
 		  else
@@ -2934,6 +2954,7 @@  variable_decl (int elem)
 
 cleanup:
   /* Free stuff up and return.  */
+  gfc_seen_div0 = false;
   gfc_free_expr (initializer);
   gfc_free_array_spec (as);