re PR c++/63366 (C++ __complex is not equivalent to __complex double)

	PR c++/63366
	* decl.c (grokdeclarator): Fix __complex meaning __complex double.

From-SVN: r217229

gcc/cp/ChangeLog

+2014-11-07  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+	PR c++/63366
+	* decl.c (grokdeclarator): Fix __complex meaning __complex double.
+
 2014-10-29  Richard Sandiford  <richard.sandiford@arm.com>
 
 	* constexpr.c: Remove redundant enum from machine_mode.

gcc/cp/decl.c

@@ -9182,11 +9182,23 @@ grokdeclarator (const cp_declarator *declarator,
     }
   /* No type at all: default to `int', and set DEFAULTED_INT
      because it was not a user-defined typedef.  */
-  if (type == NULL_TREE && (signed_p || unsigned_p || long_p || short_p))
+  if (type == NULL_TREE)
     {
-      /* These imply 'int'.  */
-      type = integer_type_node;
-      defaulted_int = 1;
+      if (signed_p || unsigned_p || long_p || short_p)
+	{
+	  /* These imply 'int'.  */
+	  type = integer_type_node;
+	  defaulted_int = 1;
+	}
+      /* If we just have "complex", it is equivalent to "complex double".  */
+      else if (!longlong && !explicit_intN
+	       && decl_spec_seq_has_spec_p (declspecs, ds_complex))
+	{
+	  type = double_type_node;
+	  pedwarn (declspecs->locations[ds_complex], OPT_Wpedantic,
+		   "ISO C++ does not support plain %<complex%> meaning "
+		   "%<double complex%>");
+	}
     }
   /* Gather flags.  */
   explicit_int = declspecs->explicit_int_p;
@@ -9371,13 +9383,8 @@ grokdeclarator (const cp_declarator *declarator,
     {
       if (TREE_CODE (type) != INTEGER_TYPE && TREE_CODE (type) != REAL_TYPE)
 	error ("complex invalid for %qs", name);
-      /* If we just have "complex", it is equivalent to
-	 "complex double", but if any modifiers at all are specified it is
-	 the complex form of TYPE.  E.g, "complex short" is
-	 "complex short int".  */
-      else if (defaulted_int && ! longlong && ! explicit_intN
-	       && ! (long_p || short_p || signed_p || unsigned_p))
-	type = complex_double_type_node;
+      /* If a modifier is specified, the resulting complex is the complex
+	 form of TYPE.  E.g, "complex short" is "complex short int".  */
       else if (type == integer_type_node)
 	type = complex_integer_type_node;
       else if (type == float_type_node)

gcc/testsuite/g++.dg/torture/pr63366.C

+// { dg-do run }
+// { dg-options "-pedantic" }
+
+#include <typeinfo>
+
+int
+main (void)
+{
+  return typeid (__complex) != typeid (__complex double); /* { dg-warning "ISO C\\+\\+ does not support plain 'complex' meaning 'double complex'" } */
+}