re PR c++/78890 (ICE on invalid reference type in union)

	PR c++/78890
	* class.c (check_field_decls): Diagnose REFERENCE_TYPE fields in
	unions even for C++11 and later.

	* g++.dg/init/ref14.C: Expect error even in C++11 and later.
	* g++.dg/init/union1.C: Likewise.
	* g++.dg/cpp0x/union6.C: Expect errors.
	* g++.dg/cpp0x/union8.C: New test.
	* g++.dg/cpp0x/pr78890-1.C: New test.
	* g++.dg/cpp0x/pr78890-2.C: New test.

From-SVN: r244112

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 35f0a2222ac206a4a3dfeb23b90b5fe3c0839405..5bc7d5217686ac23de21c3222aeab5aefa173577 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2017-01-05  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c++/78890
+       * class.c (check_field_decls): Diagnose REFERENCE_TYPE fields in
+       unions even for C++11 and later.
+
 2017-01-05  Nathan Sidwell  <nathan@acm.org>
 
        PR c++/78765

diff --git a/gcc/cp/class.c b/gcc/cp/class.c
index 1c6b401ec65056778a608b1e9afc2dafbf59c532..b7c26a1829f53d9ce05eb1cbcbef0c753b2ec68d 100644 (file)
--- a/gcc/cp/class.c
+++ b/gcc/cp/class.c
@@ -3759,25 +3759,27 @@ check_field_decls (tree t, tree *access_decls,
       /* When this goes into scope, it will be a non-local reference.  */
       DECL_NONLOCAL (x) = 1;
 
-      if (TREE_CODE (t) == UNION_TYPE
-         && cxx_dialect < cxx11)
+      if (TREE_CODE (t) == UNION_TYPE)
        {
          /* [class.union] (C++98)
 
             If a union contains a static data member, or a member of
             reference type, the program is ill-formed.
 
-            In C++11 this limitation doesn't exist anymore.  */
-         if (VAR_P (x))
+            In C++11 [class.union] says:
+            If a union contains a non-static data member of reference type
+            the program is ill-formed.  */
+         if (VAR_P (x) && cxx_dialect < cxx11)
            {
              error ("in C++98 %q+D may not be static because it is "
                     "a member of a union", x);
              continue;
            }
-         if (TREE_CODE (type) == REFERENCE_TYPE)
+         if (TREE_CODE (type) == REFERENCE_TYPE
+             && TREE_CODE (x) == FIELD_DECL)
            {
-             error ("in C++98 %q+D may not have reference type %qT "
-                    "because it is a member of a union", x, type);
+             error ("non-static data member %q+D in a union may not "
+                    "have reference type %qT", x, type);
              continue;
            }
        }

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index de407c40250ac1f4dbeef4bc93aa18bd27c026e0..c992d7139219c280a2f047f0d290017b830d4334 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,13 @@
+2017-01-05  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c++/78890
+       * g++.dg/init/ref14.C: Expect error even in C++11 and later.
+       * g++.dg/init/union1.C: Likewise.
+       * g++.dg/cpp0x/union6.C: Expect errors.
+       * g++.dg/cpp0x/union8.C: New test.
+       * g++.dg/cpp0x/pr78890-1.C: New test.
+       * g++.dg/cpp0x/pr78890-2.C: New test.
+
 2017-01-05  David Edelsohn  <dje.gcc@gmail.com>
 
        * gcc.target/powerpc/pr71670.c: Require p9vector.

diff --git a/gcc/testsuite/g++.dg/cpp0x/pr78890-1.C b/gcc/testsuite/g++.dg/cpp0x/pr78890-1.C
new file mode 100644 (file)
index 0000000..6fccc4f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/pr78890-1.C
@@ -0,0 +1,13 @@
+// PR c++/78890
+// { dg-do compile { target c++11 } }
+
+int
+main()
+{
+  union {
+    int a;
+    int &b = a;                // { dg-error "may not have reference type" }
+  };
+  a = 1;
+  auto c = b + 1;
+}

diff --git a/gcc/testsuite/g++.dg/cpp0x/pr78890-2.C b/gcc/testsuite/g++.dg/cpp0x/pr78890-2.C
new file mode 100644 (file)
index 0000000..0a11bf4
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/pr78890-2.C
@@ -0,0 +1,44 @@
+// PR c++/78890
+// { dg-do compile { target c++11 } }
+
+template <typename T>
+int
+foo ()
+{
+  union {
+    int a;
+    int &b = a;                        // { dg-error "may not have reference type" }
+  };
+  a = 1;
+  auto c = b + 1;
+  return c;
+}
+
+template <typename T>
+T
+bar ()
+{
+  union {
+    T a;
+    T &b = a;                  // { dg-error "may not have reference type" }
+  };
+  a = 1;
+  auto c = b + 1;
+  return c;
+}
+
+template <typename T, typename U>
+T baz()
+{
+  union {
+    T a;
+    U b = a;                   // { dg-error "may not have reference type" }
+  };
+  a = 1;
+  auto c = b + 1;
+  return c;
+}
+
+int a = foo<int> ();
+int b = bar<int> ();
+int c = baz<int, int &> ();

diff --git a/gcc/testsuite/g++.dg/cpp0x/union6.C b/gcc/testsuite/g++.dg/cpp0x/union6.C
index 1706da9db59b1f248dc5a81305a81c847a56358c..408755e3195bc163402bdbc0e7a72826cbf7c52a 100644 (file)
--- a/gcc/testsuite/g++.dg/cpp0x/union6.C
+++ b/gcc/testsuite/g++.dg/cpp0x/union6.C
@@ -12,9 +12,9 @@ union Test2 {
 const int Test2::kConstant = 10;
 
 union Test3 {
-  int& kConstant;
+  int& kConstant;      // { dg-error "may not have reference type" }
 };
 
 union Test4 {
-  const int& kConstant = 10;
+  const int& kConstant = 10;   // { dg-error "may not have reference type" }
 };

diff --git a/gcc/testsuite/g++.dg/cpp0x/union8.C b/gcc/testsuite/g++.dg/cpp0x/union8.C
new file mode 100644 (file)
index 0000000..11b9656
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/union8.C
@@ -0,0 +1,26 @@
+// PR c++/78890
+// { dg-do compile { target c++11 } }
+
+union Test1 {
+  static int kConstant;
+};
+
+union Test2 {
+  static const int kConstant;
+};
+
+const int Test2::kConstant = 10;
+
+int k;
+
+union Test3 {
+  static int& kRef;
+};
+
+int& Test3::kRef = k;
+
+union Test4 {
+  static const int& kRef;
+};
+
+const int& Test4::kRef = 10;

diff --git a/gcc/testsuite/g++.dg/init/ref14.C b/gcc/testsuite/g++.dg/init/ref14.C
index 2e522c195668b777241548edb2cce9f200454597..6ac42415b4376cab478f57f2c90247e44a3c2143 100644 (file)
--- a/gcc/testsuite/g++.dg/init/ref14.C
+++ b/gcc/testsuite/g++.dg/init/ref14.C
@@ -4,7 +4,7 @@
 
 union A
 {
-  int &i; // { dg-error "may not have reference type" "" { target { ! c++11 } } }
+  int &i; // { dg-error "may not have reference type" }
 };
 
 void foo()

diff --git a/gcc/testsuite/g++.dg/init/union1.C b/gcc/testsuite/g++.dg/init/union1.C
index ea88346ebe882b9b3c9becdd3fe7fcef0a505fcf..ccae3786b12180956bf78b70ba2d2e5c500669ca 100644 (file)
--- a/gcc/testsuite/g++.dg/init/union1.C
+++ b/gcc/testsuite/g++.dg/init/union1.C
@@ -1,5 +1,5 @@
 // PR c++/14401
 
 union U {
-  int& i; // { dg-error "reference type" "" { target { ! c++11 } } }
+  int& i; // { dg-error "reference type" }
 };