diff --git a/libquadmath/ChangeLog b/libquadmath/ChangeLog
index f8e7c71303d7..3c293cfac5e0 100644
--- a/libquadmath/ChangeLog
+++ b/libquadmath/ChangeLog
@@ -1,3 +1,7 @@
+2013-02-17  Tobias Burnus  <burnus@net-b.de>
+
+	* math/cacoshq.c (cacoshq): Call signbitq instead of signbit.
+
 2013-02-06  Richard Sandiford  <rdsandiford@googlemail.com>
 
 	Revert previous patch.
diff --git a/libquadmath/math/cacoshq.c b/libquadmath/math/cacoshq.c
index 263e03d0c112..a7025dc917dc 100644
--- a/libquadmath/math/cacoshq.c
+++ b/libquadmath/math/cacoshq.c
@@ -70,7 +70,7 @@ cacoshq (__complex128 x)
 	 some cases.  */
       res = 2.0Q * clogq (csqrtq ((x + 1.0Q) / 2.0Q)
 			    + csqrtq ((x - 1.0Q) / 2.0Q));
-      if (signbit (__real__ res))
+      if (signbitq (__real__ res))
 	__real__ res = 0.0Q;
     }
   else