From f85e1317f8ea933f5c615680353bd646f480f7d3 Mon Sep 17 00:00:00 2001
From: Patrick Palka <ppalka@gcc.gnu.org>
Date: Thu, 17 Dec 2015 04:01:47 +0000
Subject: [PATCH] Fix some blockers of PR c++/24666 (arrays decay to pointers
 too early)

gcc/cp/ChangeLog:

	PR c++/16333
	PR c++/41426
	PR c++/59878
	PR c++/66895
	* typeck.c (convert_for_initialization): Don't perform an early
	decaying conversion if converting to a class type.

gcc/testsuite/ChangeLog:

	PR c++/16333
	PR c++/41426
	PR c++/59878
	PR c++/66895
	* g++.dg/conversion/pr16333.C: New test.
	* g++.dg/conversion/pr41426.C: New test.
	* g++.dg/conversion/pr59878.C: New test.
	* g++.dg/conversion/pr66895.C: New test.

From-SVN: r231736
---
 gcc/cp/ChangeLog                          |  9 +++++
 gcc/cp/typeck.c                           | 16 +++++----
 gcc/testsuite/ChangeLog                   | 11 +++++++
 gcc/testsuite/g++.dg/conversion/pr16333.C | 10 ++++++
 gcc/testsuite/g++.dg/conversion/pr41426.C | 40 +++++++++++++++++++++++
 gcc/testsuite/g++.dg/conversion/pr59878.C | 25 ++++++++++++++
 gcc/testsuite/g++.dg/conversion/pr66895.C | 16 +++++++++
 7 files changed, 120 insertions(+), 7 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/conversion/pr16333.C
 create mode 100644 gcc/testsuite/g++.dg/conversion/pr41426.C
 create mode 100644 gcc/testsuite/g++.dg/conversion/pr59878.C
 create mode 100644 gcc/testsuite/g++.dg/conversion/pr66895.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 91bc456399f..14292e9fab3 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,12 @@
+2015-12-16  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/16333
+	PR c++/41426
+	PR c++/59878
+	PR c++/66895
+	* typeck.c (convert_for_initialization): Don't perform an early
+	decaying conversion if converting to a class type.
+
 2015-12-16  Patrick Palka  <ppalka@gcc.gnu.org>
 
 	* tree.c (cp_tree_operand_length): Define in terms of
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 39c1af2f257..a06ecf0732a 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -8479,13 +8479,15 @@ convert_for_initialization (tree exp, tree type, tree rhs, int flags,
       || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
     return error_mark_node;
 
-  if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
-       && TREE_CODE (type) != ARRAY_TYPE
-       && (TREE_CODE (type) != REFERENCE_TYPE
-	   || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
-      || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
-	  && !TYPE_REFFN_P (type))
-      || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
+  if (MAYBE_CLASS_TYPE_P (non_reference (type)))
+    ;
+  else if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
+	    && TREE_CODE (type) != ARRAY_TYPE
+	    && (TREE_CODE (type) != REFERENCE_TYPE
+		|| TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
+	   || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
+	       && !TYPE_REFFN_P (type))
+	   || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
     rhs = decay_conversion (rhs, complain);
 
   rhstype = TREE_TYPE (rhs);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 0a8723080fd..697fd0667b8 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,14 @@
+2015-12-16  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/16333
+	PR c++/41426
+	PR c++/59878
+	PR c++/66895
+	* g++.dg/conversion/pr16333.C: New test.
+	* g++.dg/conversion/pr41426.C: New test.
+	* g++.dg/conversion/pr59878.C: New test.
+	* g++.dg/conversion/pr66895.C: New test.
+
 2015-12-16  Martin Sebor  <msebor@redhat.com>
 
 	PR c/68868
diff --git a/gcc/testsuite/g++.dg/conversion/pr16333.C b/gcc/testsuite/g++.dg/conversion/pr16333.C
new file mode 100644
index 00000000000..810c12a9acb
--- /dev/null
+++ b/gcc/testsuite/g++.dg/conversion/pr16333.C
@@ -0,0 +1,10 @@
+// PR c++/16333
+
+struct X {
+   X (const int (&)[3]);
+};
+
+int a[3];
+X foo1 () { return a; }
+const X &foo2 () { return a; } // { dg-warning "returning reference to temporary" }
+X &foo3 () { return a; } // { dg-error "invalid initialization" }
diff --git a/gcc/testsuite/g++.dg/conversion/pr41426.C b/gcc/testsuite/g++.dg/conversion/pr41426.C
new file mode 100644
index 00000000000..78ec5fbdfbf
--- /dev/null
+++ b/gcc/testsuite/g++.dg/conversion/pr41426.C
@@ -0,0 +1,40 @@
+// PR c++/41426
+
+template <typename _T>
+struct A
+{
+   template <int _N>
+       A(_T (&V)[_N]);
+   A();
+};
+
+A<float> g1()
+{
+   float f[] = {1.1f, 2.3f};
+   return f;
+}
+
+const A<float> &g3()
+{
+   float f[] = {1.1f, 2.3f};
+   return f; // { dg-warning "returning reference to temporary" }
+}
+
+A<float> &g4()
+{
+   float f[] = {1.1f, 2.3f};
+   return f; // { dg-error "invalid initialization" }
+}
+
+struct B
+{
+   B (int (&v)[10]);
+   B();
+};
+
+B g2()
+{
+   int c[10];
+   return c;
+}
+
diff --git a/gcc/testsuite/g++.dg/conversion/pr59878.C b/gcc/testsuite/g++.dg/conversion/pr59878.C
new file mode 100644
index 00000000000..ed567fe6f24
--- /dev/null
+++ b/gcc/testsuite/g++.dg/conversion/pr59878.C
@@ -0,0 +1,25 @@
+// PR c++/59878
+
+struct Test {
+ template <int N>
+ Test(const char (&array)[N]) {}
+};
+
+Test test() {
+ return "test1";
+}
+
+void test2(Test arg = "test12") {}
+
+template <typename T>
+void test3(T arg = "test123") {}
+
+template <typename T>
+void test4(const T &arg = "test123") {}
+
+int main() {
+ test();
+ test2();
+ test3<Test>();
+ test4<Test>();
+}
diff --git a/gcc/testsuite/g++.dg/conversion/pr66895.C b/gcc/testsuite/g++.dg/conversion/pr66895.C
new file mode 100644
index 00000000000..14203bdab50
--- /dev/null
+++ b/gcc/testsuite/g++.dg/conversion/pr66895.C
@@ -0,0 +1,16 @@
+// PR c++/66895
+// { dg-do compile { target c++11 } }
+
+#include <cstddef>
+#include <initializer_list>
+
+struct S {
+    template<std::size_t N> S(char const (&)[N]);
+};
+struct T1 { S s; };
+void f1(std::initializer_list<T1>);
+void g1() { f1({{""}}); }
+
+struct T2 { const S& s; };
+void f2(std::initializer_list<T2>);
+void g2() { f2({{""}}); }
-- 
2.30.2