re PR c++/80370 (ICE when using structured bindings and nested generic lambdas (tsubs...

	PR c++/80370
	* decl.c (cp_finish_decomp): If processing_template_decl on
	non-dependent decl, only set TREE_TYPE on the v[i] decls, but don't
	change their DECL_VALUE_EXPR nor cp_finish_decl them.  Instead make
	sure DECL_VALUE_EXPR is the canonical NULL type ARRAY_REF for tsubst
	processing.
	* pt.c (value_dependent_expression_p) <case VAR_DECL>: For variables
	with DECL_VALUE_EXPR, return true if DECL_VALUE_EXPR is type
	dependent.

	* g++.dg/cpp1z/decomp28.C: New test.

From-SVN: r246857

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index e16efdccb8eadfeeb9ddd181b2502ce621233b97..c06b505b27b1753400b7d74b938aeccce53c02ca 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,15 @@
+2017-04-11  Jakub Jelinek  <jakub@redhat.com>
+
+       PR c++/80370
+       * decl.c (cp_finish_decomp): If processing_template_decl on
+       non-dependent decl, only set TREE_TYPE on the v[i] decls, but don't
+       change their DECL_VALUE_EXPR nor cp_finish_decl them.  Instead make
+       sure DECL_VALUE_EXPR is the canonical NULL type ARRAY_REF for tsubst
+       processing.
+       * pt.c (value_dependent_expression_p) <case VAR_DECL>: For variables
+       with DECL_VALUE_EXPR, return true if DECL_VALUE_EXPR is type
+       dependent.
+
 2017-04-11  Jakub Jelinek  <jakub@redhat.com>
 
        PR c++/80363

diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 516b93c3da96fd5faf3f9256f0297d5eba866623..438a4ec1c510b7e94b52a1eb022c3a79c69382e1 100644 (file)
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -7473,6 +7473,8 @@ cp_finish_decomp (tree decl, tree first, unsigned int count)
        {
          TREE_TYPE (v[i]) = eltype;
          layout_decl (v[i], 0);
+         if (processing_template_decl)
+           continue;
          tree t = unshare_expr (dexp);
          t = build4_loc (DECL_SOURCE_LOCATION (v[i]), ARRAY_REF,
                          eltype, t, size_int (i), NULL_TREE,
@@ -7492,6 +7494,8 @@ cp_finish_decomp (tree decl, tree first, unsigned int count)
        {
          TREE_TYPE (v[i]) = eltype;
          layout_decl (v[i], 0);
+         if (processing_template_decl)
+           continue;
          tree t = unshare_expr (dexp);
          t = build1_loc (DECL_SOURCE_LOCATION (v[i]),
                          i ? IMAGPART_EXPR : REALPART_EXPR, eltype,
@@ -7510,6 +7514,8 @@ cp_finish_decomp (tree decl, tree first, unsigned int count)
        {
          TREE_TYPE (v[i]) = eltype;
          layout_decl (v[i], 0);
+         if (processing_template_decl)
+           continue;
          tree t = unshare_expr (dexp);
          convert_vector_to_array_for_subscript (DECL_SOURCE_LOCATION (v[i]),
                                                 &t, size_int (i));
@@ -7559,8 +7565,9 @@ cp_finish_decomp (tree decl, tree first, unsigned int count)
              SET_DECL_VALUE_EXPR (v[i], NULL_TREE);
              DECL_HAS_VALUE_EXPR_P (v[i]) = 0;
            }
-         cp_finish_decl (v[i], init, /*constexpr*/false,
-                         /*asm*/NULL_TREE, LOOKUP_NORMAL);
+         if (!processing_template_decl)
+           cp_finish_decl (v[i], init, /*constexpr*/false,
+                           /*asm*/NULL_TREE, LOOKUP_NORMAL);
        }
     }
   else if (TREE_CODE (type) == UNION_TYPE)
@@ -7615,12 +7622,26 @@ cp_finish_decomp (tree decl, tree first, unsigned int count)
              tt = TREE_OPERAND (tt, 0);
            TREE_TYPE (v[i]) = TREE_TYPE (tt);
            layout_decl (v[i], 0);
-           SET_DECL_VALUE_EXPR (v[i], tt);
-           DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
+           if (!processing_template_decl)
+             {
+               SET_DECL_VALUE_EXPR (v[i], tt);
+               DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
+             }
            i++;
          }
     }
-  if (DECL_NAMESPACE_SCOPE_P (decl))
+  if (processing_template_decl)
+    {
+      for (unsigned int i = 0; i < count; i++)
+       if (!DECL_HAS_VALUE_EXPR_P (v[i]))
+         {
+           tree a = build_nt (ARRAY_REF, decl, size_int (i),
+                              NULL_TREE, NULL_TREE);
+           SET_DECL_VALUE_EXPR (v[i], a);
+           DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
+         }
+    }
+  else if (DECL_NAMESPACE_SCOPE_P (decl))
     SET_DECL_ASSEMBLER_NAME (decl, mangle_decomp (decl, v));
 }
 

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 5a55f179096f7f1eaab4392e86e3f16abc300444..862c2c2c08c433faf654cd089eb1b2b904573752 100644 (file)
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -23576,6 +23576,12 @@ value_dependent_expression_p (tree expression)
              || type_dependent_expression_p (DECL_INITIAL (expression))
              || value_dependent_expression_p (DECL_INITIAL (expression))))
        return true;
+      if (DECL_HAS_VALUE_EXPR_P (expression))
+       {
+         tree value_expr = DECL_VALUE_EXPR (expression);
+         if (type_dependent_expression_p (value_expr))
+           return true;
+       }
       return false;
 
     case DYNAMIC_CAST_EXPR:

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d8597e2b59709473106c963ae8dbfdc969d754c0..354adb043148599c688224e3b403de83470a3ed6 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2017-04-11  Jakub Jelinek  <jakub@redhat.com>
 
+       PR c++/80370
+       * g++.dg/cpp1z/decomp28.C: New test.
+
        PR middle-end/80100
        * gcc.dg/pr80100.c: New test.
 

diff --git a/gcc/testsuite/g++.dg/cpp1z/decomp28.C b/gcc/testsuite/g++.dg/cpp1z/decomp28.C
new file mode 100644 (file)
index 0000000..7561d9d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/decomp28.C
@@ -0,0 +1,39 @@
+// PR c++/80370
+// { dg-do compile { target c++14 } }
+// { dg-options "" }
+
+namespace std {
+  template <typename> struct tuple_size;
+  template <long, typename> struct tuple_element;
+  template <typename...> struct tuple {};
+  template <typename... T> struct tuple_size<tuple<T...>> { static constexpr int value = 1; };
+  template <typename T, typename... U> struct tuple_element<0, tuple<T, U...>> { typedef T type; };
+  template <int, typename... T> int& get (tuple<T...>);
+}
+
+template <int N>
+void
+foo (std::tuple<int> b)
+{
+  auto [c] = b;                // { dg-warning "decomposition declaration only available with" "" { target c++14_down } }
+}
+
+template <typename T>
+void
+bar (std::tuple<T> b)
+{
+  auto [c] = b;                // { dg-warning "decomposition declaration only available with" "" { target c++14_down } }
+}
+
+void
+baz (std::tuple<int> b)
+{
+  foo <5> (b);
+  bar (b);
+}
+
+int
+main ()
+{
+  [](auto) { [](std::tuple<int> b) { auto[c] = b; }; } (0); // { dg-warning "decomposition declaration only available with" "" { target c++14_down } }
+}