On 06/24/2011 08:33 AM, Diego Novillo wrote:
Patch missing.
Oopt.
commit 124387ceea38a3c0204c9f91d17bbfa68063d42e
Author: Jason Merrill <ja...@redhat.com>
Date: Wed Jun 22 16:07:10 2011 -0400
PR c++/35255
* pt.c (resolve_overloaded_unification): Fix DR 115 handling.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 08ce5af..b3dd85f 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -14524,6 +14524,7 @@ resolve_overloaded_unification (tree tparms,
the affected templates before we try to unify, in case the
explicit args will completely resolve the templates in question. */
+ int ok = 0;
tree expl_subargs = TREE_OPERAND (arg, 1);
arg = TREE_OPERAND (arg, 0);
@@ -14538,7 +14539,7 @@ resolve_overloaded_unification (tree tparms,
++processing_template_decl;
subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
expl_subargs, /*check_ret=*/false);
- if (subargs)
+ if (subargs && !any_dependent_template_arguments_p (subargs))
{
elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
if (try_one_overload (tparms, targs, tempargs, parm,
@@ -14549,8 +14550,16 @@ resolve_overloaded_unification (tree tparms,
++good;
}
}
+ else if (subargs)
+ ++ok;
--processing_template_decl;
}
+ /* If no templates (or more than one) are fully resolved by the
+ explicit arguments, this template-id is a non-deduced context; it
+ could still be OK if we deduce all template arguments for the
+ enclosing call through other arguments. */
+ if (good != 1)
+ good = ok;
}
else if (TREE_CODE (arg) != OVERLOAD
&& TREE_CODE (arg) != FUNCTION_DECL)
diff --git a/gcc/testsuite/g++.dg/template/partial10.C b/gcc/testsuite/g++.dg/template/partial10.C
new file mode 100644
index 0000000..53a48fb
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/partial10.C
@@ -0,0 +1,18 @@
+// PR c++/35255, DR 115
+// { dg-do link }
+
+// 14.8.1: In contexts where deduction is done and fails, or in contexts
+// where deduction is not done, if a template argument list is specified
+// and it, along with any default template arguments, identifies a single
+// function template specialization, then the template-id is an lvalue for
+// the function template specialization.
+
+template <class Fn> void def(Fn fn) {}
+
+template <class T1, class T2> T2 fn(T1, T2);
+template <class T1> int fn(T1) { }
+
+int main()
+{
+ def(fn<int>);
+}
diff --git a/gcc/testsuite/g++.dg/template/partial11.C b/gcc/testsuite/g++.dg/template/partial11.C
new file mode 100644
index 0000000..b5ceaa8
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/partial11.C
@@ -0,0 +1,24 @@
+// DR 115
+
+// 14.8.1: In contexts where deduction is done and fails, or in contexts
+// where deduction is not done, if a template argument list is specified
+// and it, along with any default template arguments, identifies a single
+// function template specialization, then the template-id is an lvalue for
+// the function template specialization.
+
+// Here, deduction is not done to resolve fn<int> because the target type
+// is a template parameter, so we resolve to the second template, and then
+// the call to def fails because we deduce different values of Fn for the
+// two function arguments.
+
+template <class Fn> void def(Fn fn, Fn fn2);
+
+template <class T1, class T2> T2 fn(T1, T2);
+template <class T1> int fn(T1);
+
+int f(int,int);
+
+int main()
+{
+ def(fn<int>,f); // { dg-error "" }
+}
