re PR fortran/47348 (wrong string length with array constructor)

2011-02-19  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/47348
	* trans-array.c (get_array_ctor_all_strlen): Move up in file.
	(get_array_ctor_var_strlen): Add block dummy and add call to
	get_array_ctor_all_strlen instead of giving up on substrings.
	Call gcc_unreachable for default case.
	(get_array_ctor_strlen): Add extra argument to in call to
	get_array_ctor_var_strlen.

2011-02-19  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/47348
	* gfortran.dg/array_constructor_36.f90 : New test.
	* gfortran.dg/bounds_check_10.f90 : Change dg-output message to
	allow for comparison between different elements of the array
	constructor at different levels of optimization.

From-SVN: r170317

gcc/fortran/ChangeLog

+2011-02-19  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/47348
+	* trans-array.c (get_array_ctor_all_strlen): Move up in file.
+	(get_array_ctor_var_strlen): Add block dummy and add call to
+	get_array_ctor_all_strlen instead of giving up on substrings.
+	Call gcc_unreachable for default case.
+	(get_array_ctor_strlen): Add extra argument to in call to
+	get_array_ctor_var_strlen.
+
 2011-02-18  Janus Weil  <janus@gcc.gnu.org>
 
 	PR fortran/47789

gcc/fortran/trans-array.c

@@ -1495,11 +1495,55 @@ gfc_trans_array_constructor_value (stmtblock_t * pblock, tree type,
 }
 
 
+/* A catch-all to obtain the string length for anything that is not a
+   a substring of non-constant length, a constant, array or variable.  */
+
+static void
+get_array_ctor_all_strlen (stmtblock_t *block, gfc_expr *e, tree *len)
+{
+  gfc_se se;
+  gfc_ss *ss;
+
+  /* Don't bother if we already know the length is a constant.  */
+  if (*len && INTEGER_CST_P (*len))
+    return;
+
+  if (!e->ref && e->ts.u.cl && e->ts.u.cl->length
+	&& e->ts.u.cl->length->expr_type == EXPR_CONSTANT)
+    {
+      /* This is easy.  */
+      gfc_conv_const_charlen (e->ts.u.cl);
+      *len = e->ts.u.cl->backend_decl;
+    }
+  else
+    {
+      /* Otherwise, be brutal even if inefficient.  */
+      ss = gfc_walk_expr (e);
+      gfc_init_se (&se, NULL);
+
+      /* No function call, in case of side effects.  */
+      se.no_function_call = 1;
+      if (ss == gfc_ss_terminator)
+	gfc_conv_expr (&se, e);
+      else
+	gfc_conv_expr_descriptor (&se, e, ss);
+
+      /* Fix the value.  */
+      *len = gfc_evaluate_now (se.string_length, &se.pre);
+
+      gfc_add_block_to_block (block, &se.pre);
+      gfc_add_block_to_block (block, &se.post);
+
+      e->ts.u.cl->backend_decl = *len;
+    }
+}
+
+
 /* Figure out the string length of a variable reference expression.
    Used by get_array_ctor_strlen.  */
 
 static void
-get_array_ctor_var_strlen (gfc_expr * expr, tree * len)
+get_array_ctor_var_strlen (stmtblock_t *block, gfc_expr * expr, tree * len)
 {
   gfc_ref *ref;
   gfc_typespec *ts;
@@ -1526,7 +1570,11 @@ get_array_ctor_var_strlen (gfc_expr * expr, tree * len)
 	case REF_SUBSTRING:
 	  if (ref->u.ss.start->expr_type != EXPR_CONSTANT
 	      || ref->u.ss.end->expr_type != EXPR_CONSTANT)
-	    break;
+	    {
+	      /* Note that this might evaluate expr.  */
+	      get_array_ctor_all_strlen (block, expr, len);
+	      return;
+	    }
 	  mpz_init_set_ui (char_len, 1);
 	  mpz_add (char_len, char_len, ref->u.ss.end->value.integer);
 	  mpz_sub (char_len, char_len, ref->u.ss.start->value.integer);
@@ -1536,10 +1584,7 @@ get_array_ctor_var_strlen (gfc_expr * expr, tree * len)
 	  return;
 
 	default:
-	  /* TODO: Substrings are tricky because we can't evaluate the
-	     expression more than once.  For now we just give up, and hope
-	     we can figure it out elsewhere.  */
-	  return;
+	 gcc_unreachable ();
 	}
     }
 
@@ -1547,49 +1592,6 @@ get_array_ctor_var_strlen (gfc_expr * expr, tree * len)
 }
 
 
-/* A catch-all to obtain the string length for anything that is not a
-   constant, array or variable.  */
-static void
-get_array_ctor_all_strlen (stmtblock_t *block, gfc_expr *e, tree *len)
-{
-  gfc_se se;
-  gfc_ss *ss;
-
-  /* Don't bother if we already know the length is a constant.  */
-  if (*len && INTEGER_CST_P (*len))
-    return;
-
-  if (!e->ref && e->ts.u.cl && e->ts.u.cl->length
-	&& e->ts.u.cl->length->expr_type == EXPR_CONSTANT)
-    {
-      /* This is easy.  */
-      gfc_conv_const_charlen (e->ts.u.cl);
-      *len = e->ts.u.cl->backend_decl;
-    }
-  else
-    {
-      /* Otherwise, be brutal even if inefficient.  */
-      ss = gfc_walk_expr (e);
-      gfc_init_se (&se, NULL);
-
-      /* No function call, in case of side effects.  */
-      se.no_function_call = 1;
-      if (ss == gfc_ss_terminator)
-	gfc_conv_expr (&se, e);
-      else
-	gfc_conv_expr_descriptor (&se, e, ss);
-
-      /* Fix the value.  */
-      *len = gfc_evaluate_now (se.string_length, &se.pre);
-
-      gfc_add_block_to_block (block, &se.pre);
-      gfc_add_block_to_block (block, &se.post);
-
-      e->ts.u.cl->backend_decl = *len;
-    }
-}
-
-
 /* Figure out the string length of a character array constructor.
    If len is NULL, don't calculate the length; this happens for recursive calls
    when a sub-array-constructor is an element but not at the first position,
@@ -1633,7 +1635,7 @@ get_array_ctor_strlen (stmtblock_t *block, gfc_constructor_base base, tree * len
 	case EXPR_VARIABLE:
 	  is_const = false;
 	  if (len)
-	    get_array_ctor_var_strlen (c->expr, len);
+	    get_array_ctor_var_strlen (block, c->expr, len);
 	  break;
 
 	default:

gcc/testsuite/ChangeLog

+2011-02-19  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/47348
+	* trans-array.c (get_array_ctor_all_strlen): Move up in file.
+	(get_array_ctor_var_strlen): Add block dummy and add call to
+	get_array_ctor_all_strlen instead of giving up on substrings.
+	Call gcc_unreachable for default case.
+	(get_array_ctor_strlen): Add extra argument to in call to
+	get_array_ctor_var_strlen.
+
+2011-02-19  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/47348
+	* gfortran.dg/array_constructor_36.f90 : New test.
+	* gfortran.dg/bounds_check_10.f90 : Change dg-output message to
+	allow for comparison between different elements of the array
+	constructor at different levels of optimization.
+
 2011-02-19  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* gcc.target/i386/pr31167.c: Require int128 instead of lp64.

gcc/testsuite/gfortran.dg/array_constructor_36.f90

+! { dg-do run }
+! Test the fix for PR47348, in which the substring length
+! in the array constructor at line 19 would be missed and
+! the length of q used instead.
+!
+! Contributed by Thomas Koenig  <tkoenig@netcologne.de>
+!
+program main
+  implicit none
+  character(len = *), parameter :: fmt='(2(A,"|"))'
+  character(len = *), parameter :: test='xyc|aec|'
+  integer :: i
+  character(len = 4) :: q
+  character(len = 8) :: buffer
+  q = 'xy'
+  i = 2
+  write (buffer, fmt) (/ trim(q), 'ae' /)//'c'
+  if (buffer .ne. test) Call abort
+  write (buffer, FMT) (/ q(1:i), 'ae' /)//'c'
+  if (buffer .ne. test) Call abort
+end program main

gcc/testsuite/gfortran.dg/bounds_check_10.f90

@@ -12,4 +12,4 @@ z = [y(1:1), y(1:1), x(1:len(trim(x)))]  ! should work
 z = [trim(x), trim(y), "aaaa"] ! [ "a", "cd", "aaaa" ] should catch first error
 end program array_char
 
-! { dg-output "Different CHARACTER lengths .1/2. in array constructor" }
+! { dg-output "Different CHARACTER lengths .1/.. in array constructor" }