re PR c++/48138 (__attribute__((aligned)) should give an error when applied to a…

re PR c++/48138 (__attribute__((aligned)) should give an error when applied to a typedef or template parameter, at least in C++0x mode.)

	PR c++/48138
	* tree.c (strip_typedefs): Use build_aligned_type.

From-SVN: r175215

gcc/cp/ChangeLog

 2011-06-20  Jason Merrill  <jason@redhat.com>
 
+	PR c++/48138
+	* tree.c (strip_typedefs): Use build_aligned_type.
+
 	PR c++/49205
 	* call.c (sufficient_parms_p): Allow parameter packs too.
 

gcc/cp/tree.c

@@ -1167,6 +1167,16 @@ strip_typedefs (tree t)
 
   if (!result)
       result = TYPE_MAIN_VARIANT (t);
+  if (TYPE_USER_ALIGN (t) != TYPE_USER_ALIGN (result)
+      || TYPE_ALIGN (t) != TYPE_ALIGN (result))
+    {
+      gcc_assert (TYPE_USER_ALIGN (t));
+      if (TYPE_ALIGN (t) == TYPE_ALIGN (result))
+	result = build_variant_type_copy (result);
+      else
+	result = build_aligned_type (result, TYPE_ALIGN (t));
+      TYPE_USER_ALIGN (result) = true;
+    }
   if (TYPE_ATTRIBUTES (t))
     result = cp_build_type_attribute_variant (result, TYPE_ATTRIBUTES (t));
   return cp_build_qualified_type (result, cp_type_quals (t));

gcc/testsuite/ChangeLog

 2011-06-20  Jason Merrill  <jason@redhat.com>
 
+	PR c++/48138
+	* g++.dg/ext/attr-aligned01.C: New.
+
 	PR c++/49205
 	* g++.dg/cpp0x/variadic-default.C: New.
 

gcc/testsuite/g++.dg/ext/attr-aligned01.C

+// PR c++/48138
+// { dg-options -std=c++0x }
+
+#define ALIGNED(x) __attribute__((aligned(x)))
+#define SA(X) static_assert ((X),#X)
+
+template<typename T>
+void type_alignment(const T&) {
+  struct { char c; T t; } s;
+  SA((char*)&s.t - (char*)&s.c == 8);
+}
+
+int main() {
+  typedef char unaligned[15];
+  typedef char aligned[15] ALIGNED(8);
+
+  aligned z;
+  type_alignment(z);
+  type_alignment<unaligned ALIGNED(8)>(z);
+}