Revert "Fix the remaining PR c++/24666 blockers"

gcc/cp/ChangeLog:

	Revert:
	2016-01-18  Patrick Palka  <ppalka@gcc.gnu.org>

	PR c++/11858
	PR c++/24663
	PR c++/24664
	* decl.c (grokdeclarator): Don't decay array parameter type to
	a pointer type if it's dependent.
	(grokparms): Invoke strip_top_quals instead of directly invoking
	cp_build_qualified_type.
	* pt.c (decay_dependent_array_parm_type): New static function.
	(type_unification_real): Call decay_dependent_array_parm_type
	to decay a dependent array parameter type to its corresponding
	pointer type before unification.
	(more_specialized_fn): Likewise.
	(get_bindings): Likewise.
	* tree.c (cp_build_qualified_type): Trivial typofix in
	documentation.

gcc/testsuite/ChangeLog:

	Revert:
	2016-01-18  Patrick Palka  <ppalka@gcc.gnu.org>

	PR c++/11858
	PR c++/24663
	PR c++/24664
	* g++.dg/template/pr11858.C: New test.
	* g++.dg/template/pr24663.C: New test.
	* g++.dg/template/unify12.C: New test.
	* g++.dg/template/unify13.C: New test.
	* g++.dg/template/unify14.C: New test.
	* g++.dg/template/unify15.C: New test.
	* g++.dg/template/unify16.C: New test.
	* g++.dg/template/unify17.C: New test.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@232778 138bc75d-0d04-0410-961f-82ee72b054a4

13 files changed, 43 insertions, 222 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 07fcef44987..ee5d0c0748d 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,24 @@
+2016-01-24  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	Revert:
+	2016-01-18  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/11858
+	PR c++/24663
+	PR c++/24664
+	* decl.c (grokdeclarator): Don't decay array parameter type to
+	a pointer type if it's dependent.
+	(grokparms): Invoke strip_top_quals instead of directly invoking
+	cp_build_qualified_type.
+	* pt.c (decay_dependent_array_parm_type): New static function.
+	(type_unification_real): Call decay_dependent_array_parm_type
+	to decay a dependent array parameter type to its corresponding
+	pointer type before unification.
+	(more_specialized_fn): Likewise.
+	(get_bindings): Likewise.
+	* tree.c (cp_build_qualified_type): Trivial typofix in
+	documentation.
+
 2016-01-23  Martin Sebor  <msebor@redhat.com>
 
 	PR c++/58109
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index f4604b61ee0..d8915fde209 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -10898,13 +10898,8 @@ grokdeclarator (const cp_declarator *declarator,
 
       if (TREE_CODE (type) == ARRAY_TYPE)
 	{
-	  /* Withhold decaying a dependent array type so that that during
-	     instantiation we can detect type deduction failure cases such as
-	     creating an array of void, creating a zero-size array, etc.  */
-	  if (dependent_type_p (type))
-	    ;
-	  else
-	    type = build_pointer_type (TREE_TYPE (type));
+	  /* Transfer const-ness of array into that of type pointed to.  */
+	  type = build_pointer_type (TREE_TYPE (type));
 	  type_quals = TYPE_UNQUALIFIED;
 	  array_parameter_p = true;
 	}
@@ -11705,8 +11700,7 @@ grokparms (tree parmlist, tree *parms)
 
 	  /* Top-level qualifiers on the parameters are
 	     ignored for function types.  */
-	  type = strip_top_quals (type);
-
+	  type = cp_build_qualified_type (type, 0);
 	  if (TREE_CODE (type) == METHOD_TYPE)
 	    {
 	      error ("parameter %qD invalidly declared method type", decl);
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 7985198d46c..186a5d278b8 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -17789,23 +17789,6 @@ fn_type_unification (tree fn,
   return r;
 }
 
-/* TYPE is the type of a function parameter.  If TYPE is a (dependent)
-   ARRAY_TYPE, return the corresponding POINTER_TYPE to which it decays.
-   Otherwise return TYPE.  (We shouldn't see non-dependent ARRAY_TYPE
-   parameters because they get decayed as soon as they are declared.)  */
-
-static tree
-decay_dependent_array_parm_type (tree type)
-{
-  if (TREE_CODE (type) == ARRAY_TYPE)
-    {
-      gcc_assert (uses_template_parms (type));
-      return type_decays_to (type);
-    }
-
-  return type;
-}
-
 /* Adjust types before performing type deduction, as described in
    [temp.deduct.call] and [temp.deduct.conv].  The rules in these two
    sections are symmetric.  PARM is the type of a function parameter
@@ -18244,8 +18227,6 @@ type_unification_real (tree tparms,
       arg = args[ia];
       ++ia;
 
-      parm = decay_dependent_array_parm_type (parm);
-
       if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
 			      explain_p))
 	return 1;
@@ -20257,9 +20238,6 @@ more_specialized_fn (tree pat1, tree pat2, int len)
           len = 0;
         }
 
-      arg1 = decay_dependent_array_parm_type (arg1);
-      arg2 = decay_dependent_array_parm_type (arg2);
-
       if (TREE_CODE (arg1) == REFERENCE_TYPE)
 	{
 	  ref1 = TYPE_REF_IS_RVALUE (arg1) + 1;
@@ -20545,10 +20523,7 @@ get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
   for (arg = decl_arg_types, ix = 0;
        arg != NULL_TREE && arg != void_list_node;
        arg = TREE_CHAIN (arg), ++ix)
-    {
-      args[ix] = TREE_VALUE (arg);
-      args[ix] = decay_dependent_array_parm_type (args[ix]);
-    }
+    args[ix] = TREE_VALUE (arg);
 
   if (fn_type_unification (fn, explicit_args, targs,
 			   args, ix,
diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c
index e2123ac5179..d4cf3102a03 100644
--- a/gcc/cp/tree.c
+++ b/gcc/cp/tree.c
@@ -1012,7 +1012,7 @@ c_build_qualified_type (tree type, int type_quals, tree /* orig_qual_type */,
    arrays correctly.  In particular, if TYPE is an array of T's, and
    TYPE_QUALS is non-empty, returns an array of qualified T's.
 
-   COMPLAIN determines how to deal with ill-formed qualifications. If
+   FLAGS determines how to deal with ill-formed qualifications. If
    tf_ignore_bad_quals is set, then bad qualifications are dropped
    (this is permitted if TYPE was introduced via a typedef or template
    type parameter). If bad qualifications are dropped and tf_warning
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 4fb8cca07cd..95f49032225 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,20 @@
+2016-01-24  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	Revert:
+	2016-01-18  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/11858
+	PR c++/24663
+	PR c++/24664
+	* g++.dg/template/pr11858.C: New test.
+	* g++.dg/template/pr24663.C: New test.
+	* g++.dg/template/unify12.C: New test.
+	* g++.dg/template/unify13.C: New test.
+	* g++.dg/template/unify14.C: New test.
+	* g++.dg/template/unify15.C: New test.
+	* g++.dg/template/unify16.C: New test.
+	* g++.dg/template/unify17.C: New test.
+
 2016-01-24  Dominique d'Humieres  <dominiq@lps.ens.fr>
 
 	PR fortran/68283
diff --git a/gcc/testsuite/g++.dg/template/pr11858.C b/gcc/testsuite/g++.dg/template/pr11858.C
deleted file mode 100644
index dc0d6881393..00000000000
--- a/gcc/testsuite/g++.dg/template/pr11858.C
+++ /dev/null
@@ -1,5 +0,0 @@
-// PR c++/11858
-
-template <typename T> struct S { static typename T::x f (); }; // { dg-error "" }
-template <class T> int f (int [sizeof(T::f())]);
-int const i = f<S<int> >(0); // { dg-error "no matching function" }
diff --git a/gcc/testsuite/g++.dg/template/pr24663.C b/gcc/testsuite/g++.dg/template/pr24663.C
deleted file mode 100644
index 2dc68c2ed24..00000000000
--- a/gcc/testsuite/g++.dg/template/pr24663.C
+++ /dev/null
@@ -1,22 +0,0 @@
-// PR c++/24663
-
-template<int I> int f1 (char[I]);
-template<int I> int f1 (char p1 = I);
-int i = f1<0>(0);
-
-template<typename T, int I> int f2 (T[I]); // { dg-error "" }
-int j = f2<int, 0>(0); // { dg-error "no matching function" }
-int k = f2<void, 1>(0); // { dg-error "no matching function" }
-
-int o[5];
-int l = f2<int[5], 1>(&o);
-
-template<int I> int f3 (char [][I]);
-template<int I> int f3 (char p1 = I);
-int x1 = f3<1>(0); // { dg-error "is ambiguous" }
-int x2 = f3<1>();
-
-template<typename T, int I> int f4 (T [][I]); // { dg-error "" }
-int y1 = f4<void, 1>(0); // { dg-error "no matching function" }
-int y2 = f4<int (void), 1>(0); // { dg-error "no matching function" }
-int y3 = f4<int&, 1>(0); // { dg-error "no matching function" }
diff --git a/gcc/testsuite/g++.dg/template/unify12.C b/gcc/testsuite/g++.dg/template/unify12.C
deleted file mode 100644
index 6e624e41d6a..00000000000
--- a/gcc/testsuite/g++.dg/template/unify12.C
+++ /dev/null
@@ -1,46 +0,0 @@
-// { dg-do run }
-#include <cassert>
-
-template<typename T, int I> int foo (T [I][I]) { return 0; }
-
-template int foo (char [][6]);
-
-template <typename T>
-int foo (T *)
-{
-  return -1;
-}
-
-template <typename T>
-int foo (T [3][3])
-{
-  return 1;
-}
-
-template <int I>
-int foo (bool [I][I])
-{
-  return 2;
-}
-
-template <>
-int foo (bool [3][2])
-{
-  return 3;
-}
-
-char x[3];
-bool y[4];
-bool z[3][2];
-
-int a = foo (&x);
-int b = foo (&y);
-int c = foo (z);
-
-int
-main ()
-{
-  assert (a == 1);
-  assert (b == 2);
-  assert (c == 3);
-}
diff --git a/gcc/testsuite/g++.dg/template/unify13.C b/gcc/testsuite/g++.dg/template/unify13.C
deleted file mode 100644
index 56a46df7ee3..00000000000
--- a/gcc/testsuite/g++.dg/template/unify13.C
+++ /dev/null
@@ -1,26 +0,0 @@
-// { dg-do run }
-#include <cassert>
-
-template<typename T, int I> int foo (T [I][I]) { return 0; }
-
-template<typename T>
-int foo (T [3][2])
-{
-  return 1;
-}
-
-template <>
-int foo (bool [3][2])
-{
-  return 2;
-}
-
-bool z[3][2];
-
-int a = foo (z);
-
-int
-main ()
-{
-  assert (a == 2);
-}
diff --git a/gcc/testsuite/g++.dg/template/unify14.C b/gcc/testsuite/g++.dg/template/unify14.C
deleted file mode 100644
index 7fda8fd381a..00000000000
--- a/gcc/testsuite/g++.dg/template/unify14.C
+++ /dev/null
@@ -1,5 +0,0 @@
-template <typename T, int X>
-void bar (T [X]) { }
-
-template <typename T, int X>
-void bar (const T [X]) { }
diff --git a/gcc/testsuite/g++.dg/template/unify15.C b/gcc/testsuite/g++.dg/template/unify15.C
deleted file mode 100644
index fe4848b998f..00000000000
--- a/gcc/testsuite/g++.dg/template/unify15.C
+++ /dev/null
@@ -1,15 +0,0 @@
-// { dg-do run }
-#include <cassert>
-
-template <typename T, int N>
-int bar (T (&) [N]) { return 0; }
-
-template <typename T, int N>
-int bar (const T (&) [N]) { return 1; }
-
-int
-main ()
-{
-  const int s[2] = { 0 };
-  assert (bar (s) == 1);
-}
diff --git a/gcc/testsuite/g++.dg/template/unify16.C b/gcc/testsuite/g++.dg/template/unify16.C
deleted file mode 100644
index 7b5a2aa4692..00000000000
--- a/gcc/testsuite/g++.dg/template/unify16.C
+++ /dev/null
@@ -1,56 +0,0 @@
-// { dg-do run }
-#include <cassert>
-
-template <typename T>
-struct Foo
-{
-  static int foo (T) { return 0; }
-};
-
-template <typename T, int I>
-struct Foo<T[I]>
-{
-  static int foo (T[I]) { return 1; }
-};
-
-template <int I>
-struct Foo<char[I]>
-{
-  static int foo (char[I]) { return 2; }
-};
-
-template <typename T>
-struct Foo<T[5]>
-{
-  static int foo (T[5]) { return 3; }
-};
-
-template <>
-struct Foo<char[5]>
-{
-  static int foo (char[5]) { return 4; }
-};
-
-template <>
-struct Foo<const char[5]>
-{
-  static int foo (const char[5]) { return 5; }
-};
-
-int a = Foo<const char[5]>::foo (0);
-int b = Foo<char[5]>::foo (0);
-int c = Foo<bool[5]>::foo (0);
-int d = Foo<char[4]>::foo (0);
-int e = Foo<bool[4]>::foo (0);
-int f = Foo<char[]>::foo (0);
-
-int
-main (void)
-{
-  assert (a == 5);
-  assert (b == 4);
-  assert (c == 3);
-  assert (d == 2);
-  assert (e == 1);
-  assert (f == 0);
-}
diff --git a/gcc/testsuite/g++.dg/template/unify17.C b/gcc/testsuite/g++.dg/template/unify17.C
deleted file mode 100644
index 2da8553aad8..00000000000
--- a/gcc/testsuite/g++.dg/template/unify17.C
+++ /dev/null
@@ -1,11 +0,0 @@
-void foo (int *);
-
-template <typename T>
-void bar (void (T[5])); // { dg-error "array of 'void'" }
-
-void
-baz (void)
-{
-  bar (foo); // { dg-bogus "" }
-  bar<void> (0); // { dg-error "no matching function" }
-}