From 3da557ec145823c3f51ff3fa7c619d0064134800 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Fri, 16 Jun 2017 22:27:59 -0400
Subject: [PATCH] PR c++/81102 - Wrong error with partial specialization.
* pt.c (unify) [TEMPLATE_PARM_INDEX]: Strip reference when comparing
types. Do type deduction later.
From-SVN: r249320
---
gcc/cp/ChangeLog | 4 ++
gcc/cp/pt.c | 34 ++++++++--------
.../g++.dg/template/partial-specialization7.C | 40 +++++++++++++++++++
gcc/testsuite/g++.dg/template/partial5.C | 2 +-
4 files changed, 63 insertions(+), 17 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/template/partial-specialization7.C
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 330f0f205a0c..2d47d7b4a7f4 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
2017-06-16 Jason Merrill <jason@redhat.com>
+ PR c++/81102 - Wrong error with partial specialization.
+ * pt.c (unify) [TEMPLATE_PARM_INDEX]: Strip reference when comparing
+ types. Do type deduction later.
+
PR c++/80174 - ICE with partial specialization of member template.
PR c++/71747
* pt.c (get_partial_spec_bindings): Only coerce innermost args.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 0a5816303472..d2b91b243564 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -20628,18 +20628,6 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
return x;
}
- if (cxx_dialect >= cxx1z
- /* We deduce from array bounds in try_array_deduction. */
- && !(strict & UNIFY_ALLOW_INTEGER)
- && uses_template_parms (TREE_TYPE (parm))
- && !type_uses_auto (TREE_TYPE (parm)))
- {
- tree atype = TREE_TYPE (arg);
- RECUR_AND_CHECK_FAILURE (tparms, targs,
- TREE_TYPE (parm), atype,
- UNIFY_ALLOW_NONE, explain_p);
- }
-
/* [temp.deduct.type] If, in the declaration of a function template
with a non-type template-parameter, the non-type
template-parameter is used in an expression in the function
@@ -20660,7 +20648,8 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
/* Template-parameter dependent expression. Just accept it for now.
It will later be processed in convert_template_argument. */
;
- else if (same_type_p (TREE_TYPE (arg), tparm))
+ else if (same_type_p (non_reference (TREE_TYPE (arg)),
+ non_reference (tparm)))
/* OK */;
else if ((strict & UNIFY_ALLOW_INTEGER)
&& CP_INTEGRAL_TYPE_P (tparm))
@@ -20669,9 +20658,22 @@ unify (tree tparms, tree targs, tree parm, tree arg, int strict,
corresponding parameter. */
arg = fold (build_nop (tparm, arg));
else if (uses_template_parms (tparm))
- /* We haven't deduced the type of this parameter yet. Try again
- later. */
- return unify_success (explain_p);
+ {
+ /* We haven't deduced the type of this parameter yet. */
+ if (cxx_dialect >= cxx1z
+ /* We deduce from array bounds in try_array_deduction. */
+ && !(strict & UNIFY_ALLOW_INTEGER))
+ {
+ /* Deduce it from the non-type argument. */
+ tree atype = TREE_TYPE (arg);
+ RECUR_AND_CHECK_FAILURE (tparms, targs,
+ tparm, atype,
+ UNIFY_ALLOW_NONE, explain_p);
+ }
+ else
+ /* Try again later. */
+ return unify_success (explain_p);
+ }
else
return unify_type_mismatch (explain_p, tparm, TREE_TYPE (arg));
diff --git a/gcc/testsuite/g++.dg/template/partial-specialization7.C b/gcc/testsuite/g++.dg/template/partial-specialization7.C
new file mode 100644
index 000000000000..aa42191e178d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/partial-specialization7.C
@@ -0,0 +1,40 @@
+// PR c++/81102
+
+template <typename FuncSig, FuncSig f>
+struct HelperWrapper;
+
+// [...]
+
+template <typename Ret, Ret (&Func)()>
+struct HelperWrapper<Ret (&)(), Func>
+{
+ static inline int WrapFuncT(const int)
+ {
+ return 0; // Changed
+ }
+};
+
+// Unary
+template <typename Ret, typename Arg1, Ret (&Func)(Arg1)>
+struct HelperWrapper<Ret (&)(Arg1), Func>
+{
+ static inline int WrapFuncT(const int)
+ {
+ return 1; // Changed
+ }
+};
+
+// Binary
+template <typename Ret, typename Arg1, typename Arg2, Ret (&Func)(Arg1, Arg2)>
+struct HelperWrapper<Ret (&)(Arg1, Arg2), Func>
+{
+ static inline int WrapFuncT(const int)
+ {
+ return 2; // Changed
+ }
+};
+
+int main()
+{
+ return 0;
+}
diff --git a/gcc/testsuite/g++.dg/template/partial5.C b/gcc/testsuite/g++.dg/template/partial5.C
index 1b56fb39fa1f..ee45a936a0c8 100644
--- a/gcc/testsuite/g++.dg/template/partial5.C
+++ b/gcc/testsuite/g++.dg/template/partial5.C
@@ -14,7 +14,7 @@ template<typename T, typename T::foo V>
struct Y { };
template<typename T, typename U, U v>
-struct Y<T, v> { }; // { dg-error "" }
+struct Y<T, v> { }; // { dg-error "" "" { target { ! c++1z } } }
template<typename T, T V>
--
GitLab