[PATCH] PR fortran/92019 -- BOZ cannot be an array index

[Steve Kargl]

The attach patch fixes an ICE caused by the use of a bOZ as
an array index.  Tested on x86_64-*-freebsd.  OK to commit?

2019-10-09  Steven G. Kargl  <ka...@gcc.gnu.org>

        PR fortran/92019
        * array.c (match_subscript): BOZ cannot be an array subscript.
 
2019-10-09  Steven G. Kargl  <ka...@gcc.gnu.org>

        PR fortran/92019
        * gfortran.dg/pr92019.f90: New test.

-- 
Steve

Index: gcc/fortran/array.c
===================================================================
--- gcc/fortran/array.c	(revision 276705)
+++ gcc/fortran/array.c	(working copy)
@@ -66,6 +66,7 @@ match_subscript (gfc_array_ref *ar, int init, bool mat
   match m = MATCH_ERROR;
   bool star = false;
   int i;
+  bool saw_boz = false;
 
   i = ar->dimen + ar->codimen;
 
@@ -91,6 +92,12 @@ match_subscript (gfc_array_ref *ar, int init, bool mat
   else if (!star)
     m = gfc_match_expr (&ar->start[i]);
 
+  if (ar->start[i] && ar->start[i]->ts.type == BT_BOZ)
+    {
+      gfc_error ("Invalid BOZ literal constant used in subscript at %C");
+      saw_boz = true;
+    }
+
   if (m == MATCH_NO)
     gfc_error ("Expected array subscript at %C");
   if (m != MATCH_YES)
@@ -117,6 +124,12 @@ end_element:
   else
     m = gfc_match_expr (&ar->end[i]);
 
+  if (ar->end[i] && ar->end[i]->ts.type == BT_BOZ)
+    {
+      gfc_error ("Invalid BOZ literal constant used in subscript at %C");
+      saw_boz = true;
+    }
+
   if (m == MATCH_ERROR)
     return MATCH_ERROR;
 
@@ -132,6 +145,12 @@ end_element:
       m = init ? gfc_match_init_expr (&ar->stride[i])
 	       : gfc_match_expr (&ar->stride[i]);
 
+      if (ar->stride[i] && ar->stride[i]->ts.type == BT_BOZ)
+	{
+	  gfc_error ("Invalid BOZ literal constant used in subscript at %C");
+	  saw_boz = true;
+	}
+
       if (m == MATCH_NO)
 	gfc_error ("Expected array subscript stride at %C");
       if (m != MATCH_YES)
@@ -142,7 +161,7 @@ matched:
   if (star)
     ar->dimen_type[i] = DIMEN_STAR;
 
-  return MATCH_YES;
+  return (saw_boz ? MATCH_ERROR : MATCH_YES);
 }
 
 
Index: gcc/testsuite/gfortran.dg/pr92019.f90
===================================================================
--- gcc/testsuite/gfortran.dg/pr92019.f90	(nonexistent)
+++ gcc/testsuite/gfortran.dg/pr92019.f90	(working copy)
@@ -0,0 +1,9 @@
+! { dg-do compile }
+! PR fortran/92019
+program foo
+  integer :: a(4) = [1, 2, 3, 4]
+  print *, a(z'1')            ! { dg-error "Invalid BOZ literal constant" }
+  print *, a(1:z'3')          ! { dg-error "Invalid BOZ literal constant" }
+  print *, a(1:2:z'2')        ! { dg-error "Invalid BOZ literal constant" }
+  print *, a([z'2',z'1'])     ! { dg-error "cannot appear in an array constructor" }
+end program foo