PR debug/48928

	* dfp.c (decimal_to_decnumber): Handle conversion from
	dconst{1,2,m1,half}.

	* gcc.dg/dfp/pr48928.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@173606 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 29 insertions, 3 deletions

diff --git a/gcc/dfp.c b/gcc/dfp.c
index 5a18db9f52f..6e43d149cfc 100644
--- a/gcc/dfp.c
+++ b/gcc/dfp.c
@@ -1,6 +1,6 @@
 /* Decimal floating point support.
-   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Free Software
-   Foundation, Inc.
+   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011
+   Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -110,7 +110,33 @@ decimal_to_decnumber (const REAL_VALUE_TYPE *r, decNumber *dn)
         decNumberFromString (dn, "nan", &set);
       break;
     case rvc_normal:
-      gcc_assert (r->decimal);
+      if (!r->decimal)
+	{
+	  /* dconst{1,2,m1,half} are used in various places in
+	     the middle-end and optimizers, allow them here
+	     as an exception by converting them to decimal.  */
+	  if (memcmp (r, &dconst1, sizeof (*r)) == 0)
+	    {
+	      decNumberFromString (dn, "1", &set);
+	      break;
+	    }
+	  if (memcmp (r, &dconst2, sizeof (*r)) == 0)
+	    {
+	      decNumberFromString (dn, "2", &set);
+	      break;
+	    }
+	  if (memcmp (r, &dconstm1, sizeof (*r)) == 0)
+	    {
+	      decNumberFromString (dn, "-1", &set);
+	      break;
+	    }
+	  if (memcmp (r, &dconsthalf, sizeof (*r)) == 0)
+	    {
+	      decNumberFromString (dn, "0.5", &set);
+	      break;
+	    }
+	  gcc_unreachable ();
+	}
       decimal128ToNumber ((const decimal128 *) r->sig, dn);
       break;
     default: