re PR fortran/85631 (Runtime error message array bound mismatch with nonzero optimization)

2018-06-08  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/85631
	* trans.h (gfc_ss): Add field no_bounds_check.
	* trans-array.c (gfc_conv_ss_startstride): If flag_realloc_lhs and
	ss->no_bounds_check is set, do not use runtime checks.
	* trans-expr.c (gfc_trans_assignment_1): Set lss->no_bounds_check
	for reallocatable lhs.

2018-06-08  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/85631
	* gfortran.dg/bounds_check_20.f90: New test.

From-SVN: r261348

gcc/fortran/ChangeLog

+2018-06-08  Thomas Koenig  <tkoenig@gcc.gnu.org>
+
+	PR fortran/85631
+	* trans.h (gfc_ss): Add field no_bounds_check.
+	* trans-array.c (gfc_conv_ss_startstride): If flag_realloc_lhs and
+	ss->no_bounds_check is set, do not use runtime checks.
+	* trans-expr.c (gfc_trans_assignment_1): Set lss->no_bounds_check
+	for reallocatable lhs.
+
 2018-06-08  Steven G. Kargl  <kargl@gcc.gnu.org>
 
-	PR fortran/86059 
+	PR fortran/86059
 	* array.c (match_array_cons_element): NULL() cannot be in an
 	array constructor.
 

gcc/fortran/trans-array.c

@@ -4304,7 +4304,7 @@ done:
 	}
     }
 
-  /* The rest is just runtime bound checking.  */
+  /* The rest is just runtime bounds checking.  */
   if (gfc_option.rtcheck & GFC_RTCHECK_BOUNDS)
     {
       stmtblock_t block;
@@ -4334,7 +4334,7 @@ done:
 	    continue;
 
 	  /* Catch allocatable lhs in f2003.  */
-	  if (flag_realloc_lhs && ss->is_alloc_lhs)
+	  if (flag_realloc_lhs && ss->no_bounds_check)
 	    continue;
 
 	  expr = ss_info->expr;

gcc/fortran/trans-expr.c

@@ -9982,12 +9982,15 @@ gfc_trans_assignment_1 (gfc_expr * expr1, gfc_expr * expr2, bool init_flag,
 
   /* Walk the lhs.  */
   lss = gfc_walk_expr (expr1);
-  if (gfc_is_reallocatable_lhs (expr1)
-      && !(expr2->expr_type == EXPR_FUNCTION
-	   && expr2->value.function.isym != NULL
-	   && !(expr2->value.function.isym->elemental
-		|| expr2->value.function.isym->conversion)))
-    lss->is_alloc_lhs = 1;
+  if (gfc_is_reallocatable_lhs (expr1))
+    {
+      lss->no_bounds_check = 1;
+      if (!(expr2->expr_type == EXPR_FUNCTION
+	    && expr2->value.function.isym != NULL
+	    && !(expr2->value.function.isym->elemental
+		 || expr2->value.function.isym->conversion)))
+	lss->is_alloc_lhs = 1;
+    }
 
   rss = NULL;
 

gcc/fortran/trans.h

@@ -330,6 +330,7 @@ typedef struct gfc_ss
   struct gfc_loopinfo *loop;
 
   unsigned is_alloc_lhs:1;
+  unsigned no_bounds_check:1;
 }
 gfc_ss;
 #define gfc_get_ss() XCNEW (gfc_ss)

gcc/testsuite/ChangeLog

+2018-06-08  Thomas Koenig  <tkoenig@gcc.gnu.org>
+
+	PR fortran/85631
+	* gfortran.dg/bounds_check_20.f90: New test.
+
 2018-06-08  Carl Love  <cel@us.ibm.com>
 
  	* gcc.target/powerpc/p8vector-builtin-3.c: Add vec_pack test. Update
@@ -16,7 +21,7 @@
 
 2018-06-08  Steven G. Kargl  <kargl@gcc.gnu.org>
 
-	PR fortran/86059 
+	PR fortran/86059
 	* gfortran.dg/associate_30.f90: Remove code tested ...
 	* gfortran.dg/pr67803.f90: Ditto.
 	* gfortran.dg/pr67805.f90: Ditto.

gcc/testsuite/gfortran.dg/bounds_check_20.f90

+! { dg-do  run }
+! { dg-additional-options "-fcheck=bounds -ffrontend-optimize" }
+! PR 85631 - this used to cause a runtime error with bounds checking.
+module x
+contains
+  subroutine sub(a, b)
+    real, dimension(:,:), intent(in) :: a
+    real, dimension(:,:), intent(out), allocatable :: b
+    b = transpose(a)
+  end subroutine sub
+end module x
+
+program main
+  use x
+  implicit none
+  real, dimension(2,2) :: a
+  real, dimension(:,:), allocatable :: b
+  data a /-2., 3., -5., 7./
+  call sub(a, b)
+  if (any (b /= reshape([-2., -5., 3., 7.], shape(b)))) stop 1
+  b = matmul(transpose(b), a)
+  if (any (b /= reshape([-11., 15., -25.,  34.], shape(b)))) stop 2
+end program
+