https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102033
--- Comment #3 from qingzhe huang <nickhuang99 at hotmail dot com> ---
I can give tons of similar cases with even more complicated template levels
combined with using/typedefs/default arguments. i.e.
template<class TA>
struct A{
template<class TB>
struct B{
using TB_Alias=TB;
template<class TC=TB_Alias>
struct C{
typedef TC Arr3[3];
};
};
};
template<class TA, class TB>
void f(const typename A<TA>::template B<TB>::template C<>::Arr3){}
template <>
void f<int, char>(const typename A<int>::template B<char>::template
C<>::Arr3){}
The fix are all can be done similarly at point to calculating function
parameter "cv-qualifier" value by passing its result into call
*cp_build_qualified_type* at decl.c:grokparms.
for example:
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 3414cbdc876..473c7b7d75c 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -14493,7 +14493,16 @@ grokparms (tree parmlist, tree *parms)
/* Top-level qualifiers on the parameters are
ignored for function types. */
- type = cp_build_qualified_type (type, 0);
+ int type_quals = 0;
+ /* Top-level qualifiers are reserved for array type. PR101402 */
+ if (TREE_CODE (type) == TYPENAME_TYPE)
+ {
+ tree resolved_type = resolve_typename_type(type, false);
+ if (resolved_type && TREE_CODE(resolved_type) == ARRAY_TYPE)
+ type_quals = CP_TYPE_CONST_P(type);
+ }
+ type = cp_build_qualified_type (type, type_quals);
+
if (TREE_CODE (type) == METHOD_TYPE)
{
error ("parameter %qD invalidly declared method type", decl);
However, original *resolve_typename_type* function is not working well to cover
all cases. I only fixed one "non-recursive" case with
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 020a4bf2f6d..1944bf4a6ea 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -27989,7 +27989,12 @@ resolve_typename_type (tree type, bool only_current_p)
/* If we failed to resolve it, return the original typename. */
if (!result)
- return type;
+ {
+ if (TREE_CODE (fullname) == TEMPLATE_ID_EXPR
+ && TREE_CODE (decl) == TEMPLATE_DECL)
+ return TREE_TYPE(decl);
+ return type;
+ }
/* If lookup found a typename type, resolve that too. */
if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P
(result))
And then I give up because it requires almost a new *resolve_typename_type*
function to cover all possible cases. And I have no GCC write access and the
code is extremely difficult to maintain.
