re PR fortran/89843 (CFI_section delivers incorrect result descriptor)

2019-04-14  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/89843
	* trans-decl.c (gfc_get_symbol_decl): Assumed shape and assumed
	rank dummies of bind C procs require deferred initialization.
	(convert_CFI_desc): New procedure to convert incoming CFI
	descriptors to gfc types and back again.
	(gfc_trans_deferred_vars): Call it.
	* trans-expr.c (gfc_conv_gfc_desc_to_cfi_desc): Null the CFI
	descriptor pointer. Free the descriptor in all cases.

	PR fortran/89846
	* expr.c (is_CFI_desc): New function.
	(is_subref_array): Tidy up by referencing the symbol directly.
	* gfortran.h : Prototype for is_CFI_desc.
	* trans_array.c (get_CFI_desc): New function.
	(gfc_get_array_span, gfc_conv_scalarized_array_ref,
	gfc_conv_array_ref): Use it.
	* trans.c (get_array_span): Extract the span from descriptors
	that are indirect references.

	PR fortran/90022
	* trans-decl.c (gfc_get_symbol_decl): Make sure that the se
	expression is a pointer type before converting it to the symbol
	backend_decl type.
	* trans-expr.c (gfc_conv_gfc_desc_to_cfi_desc): Eliminate
	temporary creation for intent(in).

2019-04-14  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/89843
	* gfortran.dg/ISO_Fortran_binding_4.f90: Modify the value of x
	in ctg. Test the conversion of the descriptor types in the main
	program.
	* gfortran.dg/ISO_Fortran_binding_10.f90: New test.
	* gfortran.dg/ISO_Fortran_binding_10.c: Called by it.

	PR fortran/89846
	* gfortran.dg/ISO_Fortran_binding_11.f90: New test.
	* gfortran.dg/ISO_Fortran_binding_11.c: Called by it.

	PR fortran/90022
	* gfortran.dg/ISO_Fortran_binding_1.c: Correct the indexing for
	the computation of 'ans'. Also, change the expected results for
	CFI_is_contiguous to comply with standard.
	* gfortran.dg/ISO_Fortran_binding_1.f90: Correct the expected
	results for CFI_is_contiguous to comply with standard.
	* gfortran.dg/ISO_Fortran_binding_9.f90: New test.
	* gfortran.dg/ISO_Fortran_binding_9.c: Called by it.

2019-04-14  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/89843
	* runtime/ISO_Fortran_binding.c (cfi_desc_to_gfc_desc): Only
	return immediately if the source pointer is null. Bring
	forward the extraction of the gfc type. Extract the kind so
	that the element size can be correctly computed for sections
	and components of derived type arrays. Remove the free of the
	CFI descriptor since this is now done in trans-expr.c.
	(gfc_desc_to_cfi_desc): Only allocate the CFI descriptor if it
	is not null.
	(CFI_section): Normalise the difference between the upper and
	lower bounds by the stride to correctly calculate the extents
	of the section.

	PR fortran/89846
	* runtime/ISO_Fortran_binding.c (cfi_desc_to_gfc_desc): Use
	the stride measure for the gfc span if it is not a multiple
	of the element length. Otherwise use the element length.

	PR fortran/90022
	* runtime/ISO_Fortran_binding.c (CFI_is_contiguous) : Return
	1 for true and 0 otherwise to comply with the standard. Correct
	the contiguity check for rank 3 and greater by using the stride
	measure of the lower dimension rather than the element length.

From-SVN: r270353

2 files changed, 61 insertions, 30 deletions

diff --git a/libgfortran/ChangeLog b/libgfortran/ChangeLog
index 7e741b3b502..80a37fb28eb 100644
--- a/libgfortran/ChangeLog
+++ b/libgfortran/ChangeLog
@@ -1,3 +1,29 @@
+2019-04-14  Paul Thomas  <pault@gcc.gnu.org>
+
+	PR fortran/89843
+	* runtime/ISO_Fortran_binding.c (cfi_desc_to_gfc_desc): Only
+	return immediately if the source pointer is null. Bring
+	forward the extraction of the gfc type. Extract the kind so
+	that the element size can be correctly computed for sections
+	and components of derived type arrays. Remove the free of the
+	CFI descriptor since this is now done in trans-expr.c.
+	(gfc_desc_to_cfi_desc): Only allocate the CFI descriptor if it
+	is not null.
+	(CFI_section): Normalise the difference between the upper and
+	lower bounds by the stride to correctly calculate the extents
+	of the section.
+
+	PR fortran/89846
+	* runtime/ISO_Fortran_binding.c (cfi_desc_to_gfc_desc): Use
+	the stride measure for the gfc span if it is not a multiple
+	of the element length. Otherwise use the element length.
+
+	PR fortran/90022
+	* runtime/ISO_Fortran_binding.c (CFI_is_contiguous) : Return
+	1 for true and 0 otherwise to comply with the standard. Correct
+	the contiguity check for rank 3 and greater by using the stride
+	measure of the lower dimension rather than the element length.
+
 2019-03-25  John David Anglin  <danglin@gcc.gnu.org>
 
 	PR libgfortran/79540
diff --git a/libgfortran/runtime/ISO_Fortran_binding.c b/libgfortran/runtime/ISO_Fortran_binding.c
index 6b7b10fb836..695ef57ac32 100644
--- a/libgfortran/runtime/ISO_Fortran_binding.c
+++ b/libgfortran/runtime/ISO_Fortran_binding.c
@@ -37,23 +37,15 @@ void
 cfi_desc_to_gfc_desc (gfc_array_void *d, CFI_cdesc_t **s_ptr)
 {
   int n;
+  index_type kind;
   CFI_cdesc_t *s = *s_ptr;
 
-  /* If not a full pointer or allocatable array free the descriptor
-     and return.  */
-  if (!s || s->attribute == CFI_attribute_other)
-    goto finish;
+  if (!s)
+    return;
 
   GFC_DESCRIPTOR_DATA (d) = s->base_addr;
-
-  if (!s->rank || s->dim[0].sm == (CFI_index_t)s->elem_len)
-    GFC_DESCRIPTOR_SIZE (d) = s->elem_len;
-  else
-    GFC_DESCRIPTOR_SIZE (d) =  (index_type)s->dim[0].sm;
-
-  d->dtype.version = s->version;
-  GFC_DESCRIPTOR_RANK (d) = (signed char)s->rank;
   GFC_DESCRIPTOR_TYPE (d) = (signed char)(s->type & CFI_type_mask);
+  kind = (index_type)((s->type - (s->type & CFI_type_mask)) >> CFI_type_kind_shift);
 
   /* Correct the unfortunate difference in order with types.  */
   if (GFC_DESCRIPTOR_TYPE (d) == BT_CHARACTER)
@@ -61,12 +53,26 @@ cfi_desc_to_gfc_desc (gfc_array_void *d, CFI_cdesc_t **s_ptr)
   else if (GFC_DESCRIPTOR_TYPE (d) == BT_DERIVED)
     GFC_DESCRIPTOR_TYPE (d) = BT_CHARACTER;
 
+  if (!s->rank || s->dim[0].sm == (CFI_index_t)s->elem_len)
+    GFC_DESCRIPTOR_SIZE (d) = s->elem_len;
+  else if (GFC_DESCRIPTOR_TYPE (d) != BT_DERIVED)
+    GFC_DESCRIPTOR_SIZE (d) = kind;
+  else
+    GFC_DESCRIPTOR_SIZE (d) = s->elem_len;
+
+  d->dtype.version = s->version;
+  GFC_DESCRIPTOR_RANK (d) = (signed char)s->rank;
+
   d->dtype.attribute = (signed short)s->attribute;
 
   if (s->rank)
-    d->span = (index_type)s->dim[0].sm;
+    {
+      if ((size_t)s->dim[0].sm % s->elem_len)
+	d->span = (index_type)s->dim[0].sm;
+      else
+	d->span = (index_type)s->elem_len;
+    }
 
-  /* On the other hand, CFI_establish can change the bounds.  */
   d->offset = 0;
   for (n = 0; n < GFC_DESCRIPTOR_RANK (d); n++)
     {
@@ -76,11 +82,6 @@ cfi_desc_to_gfc_desc (gfc_array_void *d, CFI_cdesc_t **s_ptr)
       GFC_DESCRIPTOR_STRIDE(d, n) = (index_type)(s->dim[n].sm / s->elem_len);
       d->offset -= GFC_DESCRIPTOR_STRIDE(d, n) * GFC_DESCRIPTOR_LBOUND(d, n);
     }
-
-finish:
-  if (s)
-    free (s);
-  s = NULL;
 }
 
 extern void gfc_desc_to_cfi_desc (CFI_cdesc_t **, const gfc_array_void *);
@@ -95,8 +96,11 @@ gfc_desc_to_cfi_desc (CFI_cdesc_t **d_ptr, const gfc_array_void *s)
   /* Play it safe with allocation of the flexible array member 'dim'
      by setting the length to CFI_MAX_RANK. This should not be necessary
      but valgrind complains accesses after the allocated block.  */
-  d = malloc (sizeof (CFI_cdesc_t)
+  if (*d_ptr == NULL)
+    d = malloc (sizeof (CFI_cdesc_t)
 		+ (CFI_type_t)(CFI_MAX_RANK * sizeof (CFI_dim_t)));
+  else
+    d = *d_ptr;
 
   d->base_addr = GFC_DESCRIPTOR_DATA (s);
   d->elem_len = GFC_DESCRIPTOR_SIZE (s);
@@ -115,7 +119,7 @@ gfc_desc_to_cfi_desc (CFI_cdesc_t **d_ptr, const gfc_array_void *s)
     d->type = (CFI_type_t)(d->type
 		+ ((CFI_type_t)d->elem_len << CFI_type_kind_shift));
 
-  /* Full pointer or allocatable arrays have zero lower_bound.  */
+  /* Full pointer or allocatable arrays retain their lower_bounds.  */
   for (n = 0; n < GFC_DESCRIPTOR_RANK (s); n++)
     {
       if (d->attribute != CFI_attribute_other)
@@ -134,7 +138,8 @@ gfc_desc_to_cfi_desc (CFI_cdesc_t **d_ptr, const gfc_array_void *s)
       d->dim[n].sm = (CFI_index_t)(GFC_DESCRIPTOR_STRIDE(s, n) * s->span);
     }
 
-  *d_ptr = d;
+  if (*d_ptr == NULL)
+    *d_ptr = d;
 }
 
 void *CFI_address (const CFI_cdesc_t *dv, const CFI_index_t subscripts[])
@@ -416,7 +421,7 @@ int CFI_is_contiguous (const CFI_cdesc_t *dv)
       if (dv == NULL)
 	{
 	  fprintf (stderr, "CFI_is_contiguous: C descriptor is NULL.\n");
-	  return CFI_INVALID_DESCRIPTOR;
+	  return 0;
 	}
 
       /* Base address must not be NULL. */
@@ -424,7 +429,7 @@ int CFI_is_contiguous (const CFI_cdesc_t *dv)
 	{
 	  fprintf (stderr, "CFI_is_contiguous: Base address of C Descriptor "
 		   "is already NULL.\n");
-	  return CFI_ERROR_BASE_ADDR_NULL;
+	  return 0;
 	}
 
       /* Must be an array. */
@@ -432,13 +437,13 @@ int CFI_is_contiguous (const CFI_cdesc_t *dv)
 	{
 	  fprintf (stderr, "CFI_is_contiguous: C Descriptor must describe an "
 		   "array (0 < dv->rank = %d).\n", dv->rank);
-	  return CFI_INVALID_RANK;
+	  return 0;
 	}
     }
 
   /* Assumed size arrays are always contiguous.  */
   if (dv->rank > 0 && dv->dim[dv->rank - 1].extent == -1)
-    return CFI_SUCCESS;
+    return 1;
 
   /* If an array is not contiguous the memory stride is different to the element
    * length. */
@@ -447,15 +452,15 @@ int CFI_is_contiguous (const CFI_cdesc_t *dv)
       if (i == 0 && dv->dim[i].sm == (CFI_index_t)dv->elem_len)
 	continue;
       else if (i > 0
-	       && dv->dim[i].sm == (CFI_index_t)(dv->elem_len
+	       && dv->dim[i].sm == (CFI_index_t)(dv->dim[i - 1].sm
 				   * dv->dim[i - 1].extent))
 	continue;
 
-      return CFI_FAILURE;
+      return 0;
     }
 
   /* Array sections are guaranteed to be contiguous by the previous test.  */
-  return CFI_SUCCESS;
+  return 1;
 }
 
 
@@ -670,7 +675,7 @@ int CFI_section (CFI_cdesc_t *result, const CFI_cdesc_t *source,
 	}
       int idx = i - aux;
       result->dim[idx].lower_bound = lower[i];
-      result->dim[idx].extent = upper[i] - lower[i] + 1;
+      result->dim[idx].extent = 1 + (upper[i] - lower[i])/stride[i];
       result->dim[idx].sm = stride[i] * source->dim[i].sm;
       /* Adjust 'lower' for the base address offset.  */
       lower[idx] = lower[idx] - source->dim[i].lower_bound;