static bool
comp_template_parms_position (tree t1, tree t2)
{
+ tree index1, index2;
gcc_assert (t1 && t2
&& TREE_CODE (t1) == TREE_CODE (t2)
&& (TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM
|| TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM
|| TREE_CODE (t1) == TEMPLATE_TYPE_PARM));
- if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
- || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
- || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
- != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
- return false;
-
- return true;
-}
-
-/* Subroutine of incompatible_dependent_types_p.
- Return the template parameter of the dependent type T.
- If T is a typedef, return the template parameters of
- the _decl_ of the typedef. T must be a dependent type. */
-
-static tree
-get_template_parms_of_dependent_type (tree t)
-{
- tree tinfo = NULL_TREE, tparms = NULL_TREE;
-
- /* First, try the obvious case of getting the
- template info from T itself. */
- if ((tinfo = get_template_info (t)))
- ;
- else if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
- return TEMPLATE_TYPE_PARM_SIBLING_PARMS (t);
- else if (typedef_variant_p (t)
- && !NAMESPACE_SCOPE_P (TYPE_NAME (t)))
- tinfo = get_template_info (DECL_CONTEXT (TYPE_NAME (t)));
- /* If T is a TYPENAME_TYPE which context is a template type
- parameter, get the template parameters from that context. */
- else if (TYPE_CONTEXT (t)
- && TREE_CODE (TYPE_CONTEXT (t)) == TEMPLATE_TYPE_PARM)
- return TEMPLATE_TYPE_PARM_SIBLING_PARMS (TYPE_CONTEXT (t));
- else if (TYPE_CONTEXT (t)
- && !NAMESPACE_SCOPE_P (t))
- tinfo = get_template_info (TYPE_CONTEXT (t));
-
- if (tinfo)
- tparms = DECL_TEMPLATE_PARMS (TI_TEMPLATE (tinfo));
-
- return tparms;
-}
-
-/* Subroutine of structural_comptypes.
- Compare the dependent types T1 and T2.
- Return TRUE if we are sure they can't be equal, FALSE otherwise.
- The whole point of this function is to support cases where either T1 or
- T2 is a typedef. In those cases, we need to compare the template parameters
- of the _decl_ of the typedef. If those don't match then we know T1
- and T2 cannot be equal. */
-
-static bool
-incompatible_dependent_types_p (tree t1, tree t2)
-{
- tree tparms1 = NULL_TREE, tparms2 = NULL_TREE;
- bool t1_typedef_variant_p, t2_typedef_variant_p;
-
- if (!uses_template_parms (t1) || !uses_template_parms (t2))
- return false;
-
- if (TREE_CODE (t1) == TEMPLATE_TYPE_PARM)
- {
- /* If T1 and T2 don't have the same relative position in their
- template parameters set, they can't be equal. */
- if (!comp_template_parms_position (t1, t2))
- return true;
- }
-
- t1_typedef_variant_p = typedef_variant_p (t1);
- t2_typedef_variant_p = typedef_variant_p (t2);
+ index1 = TEMPLATE_TYPE_PARM_INDEX (TYPE_MAIN_VARIANT (t1));
+ index2 = TEMPLATE_TYPE_PARM_INDEX (TYPE_MAIN_VARIANT (t2));
- /* Either T1 or T2 must be a typedef. */
- if (!t1_typedef_variant_p && !t2_typedef_variant_p)
+ /* If T1 and T2 belong to template parm lists of different size,
+ let's assume they are different. */
+ if (TEMPLATE_PARM_NUM_SIBLINGS (index1)
+ != TEMPLATE_PARM_NUM_SIBLINGS (index2))
return false;
- if (!t1_typedef_variant_p || !t2_typedef_variant_p)
- /* Either T1 or T2 is not a typedef so we cannot compare the
- template parms of the typedefs of T1 and T2.
- At this point, if the main variant type of T1 and T2 are equal
- it means the two types can't be incompatible, from the perspective
- of this function. */
- if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
- return false;
-
- /* So if we reach this point, it means either T1 or T2 is a typedef variant.
- Let's compare their template parameters. */
-
- tparms1 = get_template_parms_of_dependent_type (t1);
- tparms2 = get_template_parms_of_dependent_type (t2);
-
- /* If T2 is a template type parm and if we could not get the template
- parms it belongs to, that means we have not finished parsing the
- full set of template parameters of the template declaration it
- belongs to yet. If we could get the template parms T1 belongs to,
- that mostly means T1 and T2 belongs to templates that are
- different and incompatible. */
- if (TREE_CODE (t1) == TEMPLATE_TYPE_PARM
- && (tparms1 == NULL_TREE || tparms2 == NULL_TREE)
- && tparms1 != tparms2)
- return true;
-
- if (tparms1 == NULL_TREE
- || tparms2 == NULL_TREE
- || tparms1 == tparms2)
+ /* Then compare their relative position. */
+ if (TEMPLATE_PARM_IDX (index1) != TEMPLATE_PARM_IDX (index2)
+ || TEMPLATE_PARM_LEVEL (index1) != TEMPLATE_PARM_LEVEL (index2)
+ || (TEMPLATE_PARM_PARAMETER_PACK (index1)
+ != TEMPLATE_PARM_PARAMETER_PACK (index2)))
return false;
- /* And now compare the mighty template parms! */
- return !comp_template_parms (tparms1, tparms2);
+ return true;
}
/* Subroutine in comptypes. */
if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
return false;
- /* If T1 and T2 are dependent typedefs then check upfront that
- the template parameters of their typedef DECLs match before
- going down checking their subtypes. */
- if (incompatible_dependent_types_p (t1, t2))
- return false;
-
/* Allow for two different type nodes which have essentially the same
definition. Note that we already checked for equality of the type
qualifiers (just above). */
break;
case TEMPLATE_TYPE_PARM:
- /* If incompatible_dependent_types_p called earlier didn't decide
- T1 and T2 were different, they might be equal. */
+ /* If T1 and T2 don't have the same relative position in their
+ template parameters set, they can't be equal. */
+ if (!comp_template_parms_position (t1, t2))
+ return false;
break;
case TYPENAME_TYPE:
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