From 29ef6cd035bda26987bd4a69a91b66908654b01b Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Tue, 5 Feb 2013 22:33:45 -0500
Subject: [PATCH] re PR c++/56208 (Some classic sfinae cases fail to work due
to access problems)
PR c++/56208
* pt.c (fn_type_unification): Discard any access checks from
substituting explicit args.
From-SVN: r195779
---
gcc/cp/ChangeLog | 6 ++++++
gcc/cp/pt.c | 6 ++++++
gcc/testsuite/g++.dg/cpp0x/sfinae43.C | 31 +++++++++++++++++++++++++++
3 files changed, 43 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/sfinae43.C
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 7bd5402a3c17..ce0bfad64f7b 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2013-02-05 Jason Merrill <jason@redhat.com>
+
+ PR c++/56208
+ * pt.c (fn_type_unification): Discard any access checks from
+ substituting explicit args.
+
2013-01-31 Jason Merrill <jason@redhat.com>
PR c++/56162
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 743028942ed2..aa127ed70992 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -14989,6 +14989,12 @@ fn_type_unification (tree fn,
if (fntype == error_mark_node)
goto fail;
+ /* Throw away these access checks; we'll see them again in
+ instantiate_template and they might have the wrong
+ access path at this point. */
+ pop_deferring_access_checks ();
+ push_deferring_access_checks (dk_deferred);
+
/* Place the explicitly specified arguments in TARGS. */
for (i = NUM_TMPL_ARGS (explicit_targs); i--;)
TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (explicit_targs, i);
diff --git a/gcc/testsuite/g++.dg/cpp0x/sfinae43.C b/gcc/testsuite/g++.dg/cpp0x/sfinae43.C
new file mode 100644
index 000000000000..22efe657fa70
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/sfinae43.C
@@ -0,0 +1,31 @@
+// PR c++/56208
+// { dg-options -std=c++11 }
+
+struct ostream {
+ ostream& operator<<(int);
+};
+
+struct sfinae_base {
+
+ typedef char one;
+ typedef char (&two)[2];
+
+ template<class T>
+ static T make();
+
+ template<unsigned> struct ok { typedef int type; };
+
+ template<class U, class T>
+ static one test(decltype((make<U>() << make<T>()), 0));
+
+ template<class, class>
+ static two test(...);
+};
+
+template<class T>
+struct is_printable : private sfinae_base
+{
+ enum { value = sizeof(test<ostream&, T>(0)) == sizeof(one) };
+};
+
+typedef int ok[is_printable<int>::value ? 1 : -1];
--
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