Patchwork C++ PATCH for c++/54903 (auto static data member template)

login
register
mail settings
Submitter Jason Merrill
Date Nov. 15, 2012, 4:10 p.m.
Message ID <50A513F7.6070704@redhat.com>
Download mbox | patch
Permalink /patch/199338/
State New
Headers show

Comments

Jason Merrill - Nov. 15, 2012, 4:10 p.m.
It's OK for a static data member of a dependent class instantiation to 
still have 'auto' type, because we can't instantiate its initializer 
yet.  So let's not bother complaining about auto decls in templates.

Tested x86_64-pc-linux-gnu, applying to trunk.

Patch

commit 10c430cf47ad234b240b06d4efdecdab0d06beeb
Author: Jason Merrill <jason@redhat.com>
Date:   Wed Nov 14 23:34:42 2012 -0500

    	PR c++/54903
    	* decl2.c (mark_used): Don't complain about auto in templates.

diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c
index 90ee16b..9f20757 100644
--- a/gcc/cp/decl2.c
+++ b/gcc/cp/decl2.c
@@ -4534,8 +4534,8 @@  mark_used (tree decl)
      it to find out its type.  */
   if ((decl_maybe_constant_var_p (decl)
        || (TREE_CODE (decl) == FUNCTION_DECL
-	   && (DECL_DECLARED_CONSTEXPR_P (decl)
-	       || type_uses_auto (TREE_TYPE (TREE_TYPE (decl))))))
+	   && DECL_DECLARED_CONSTEXPR_P (decl))
+       || type_uses_auto (TREE_TYPE (decl)))
       && DECL_LANG_SPECIFIC (decl)
       && DECL_TEMPLATE_INFO (decl)
       && !uses_template_parms (DECL_TI_ARGS (decl)))
@@ -4550,6 +4550,14 @@  mark_used (tree decl)
       --function_depth;
     }
 
+  if (processing_template_decl)
+    return true;
+
+  /* Check this too in case we're within fold_non_dependent_expr.  */
+  if (DECL_TEMPLATE_INFO (decl)
+      && uses_template_parms (DECL_TI_ARGS (decl)))
+    return true;
+
   if (type_uses_auto (TREE_TYPE (decl)))
     {
       error ("use of %qD before deduction of %<auto%>", decl);
@@ -4560,14 +4568,6 @@  mark_used (tree decl)
   if (cp_unevaluated_operand != 0)
     return true;
 
-  if (processing_template_decl)
-    return true;
-
-  /* Check this too in case we're within fold_non_dependent_expr.  */
-  if (DECL_TEMPLATE_INFO (decl)
-      && uses_template_parms (DECL_TI_ARGS (decl)))
-    return true;
-
   DECL_ODR_USED (decl) = 1;
   if (DECL_CLONED_FUNCTION_P (decl))
     DECL_ODR_USED (DECL_CLONED_FUNCTION (decl)) = 1;
diff --git a/gcc/testsuite/g++.dg/cpp0x/auto36.C b/gcc/testsuite/g++.dg/cpp0x/auto36.C
new file mode 100644
index 0000000..c353040
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/auto36.C
@@ -0,0 +1,18 @@ 
+// PR c++/54903
+// { dg-options -std=c++11 }
+
+template<int N, int D>
+struct Modulus
+{
+        static auto const value = N % D;
+};
+
+template<int N>
+struct Angle
+{
+        static auto const value = Modulus<N, 360>::value; // ERROR
+        //static int const value = Modulus<N, 360>::value;  // OK
+        //static auto const value = N % 360;                // OK
+
+        typedef Angle<value> type;
+};