re PR c/47473 (Incorrect computation with complex numbers when using -std=c99)

	PR c/47473
	* c-lex.c (interpret_float): If CPP_N_IMAGINARY, ensure
	EXCESS_PRECISION_EXPR is created with COMPLEX_TYPE instead of
	REAL_TYPE.

	* gcc.dg/torture/pr47473.c: New test.

From-SVN: r169299

gcc/c-family/ChangeLog

+2011-01-26  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/47473
+	* c-lex.c (interpret_float): If CPP_N_IMAGINARY, ensure
+	EXCESS_PRECISION_EXPR is created with COMPLEX_TYPE instead of
+	REAL_TYPE.
+
 2011-01-26  Arnaud Charlet  <charlet@adacore.com>
 
 	* c-ada-spec.c (dump_generic_ada_node): Avoid dereferencing null type.

gcc/c-family/c-lex.c

 /* Mainly the interface between cpplib and the C front ends.
    Copyright (C) 1987, 1988, 1989, 1992, 1994, 1995, 1996, 1997
-   1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
-   Free Software Foundation, Inc.
+   1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010,
+   2011 Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -752,8 +752,15 @@ interpret_float (const cpp_token *token, unsigned int flags)
   /* Create a node with determined type and value.  */
   value = build_real (const_type, real);
   if (flags & CPP_N_IMAGINARY)
-    value = build_complex (NULL_TREE, convert (const_type, integer_zero_node),
-			   value);
+    {
+      value = build_complex (NULL_TREE, convert (const_type,
+						 integer_zero_node), value);
+      if (type != const_type)
+	{
+	  const_type = TREE_TYPE (value);
+	  type = build_complex_type (type);
+	}
+    }
 
   if (type != const_type)
     value = build1 (EXCESS_PRECISION_EXPR, type, value);

gcc/testsuite/ChangeLog

+2011-01-26  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/47473
+	* gcc.dg/torture/pr47473.c: New test.
+
 2011-01-26  Jan Hubicka  <jh@suse.cz>
 
 	PR target/47237

gcc/testsuite/gcc.dg/torture/pr47473.c

+/* PR c/47473 */
+/* { dg-do run } */
+/* { dg-options "-std=c99" } */
+
+int
+main (void)
+{
+  long double _Complex w = 0.2L - 0.3iL;
+  w = w * (0.3L - (0.0F + 1.0iF) * 0.9L);
+  if (__builtin_fabsl (__real__ w + 0.21L) > 0.001L
+      || __builtin_fabsl (__imag__ w + 0.27L) > 0.001L)
+    __builtin_abort ();
+  return 0;
+}