diff --git a/ChangeLog b/ChangeLog
index ba42b5bd28..c08b711d7a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2016-12-14  Joseph Myers  <joseph@codesourcery.com>
 
+	[BZ #20947]
+	* math/s_fmax_template.c (M_DECL_FUNC (__fmax)): Add the arguments
+	when either is a signaling NaN.
+	* math/s_fmin_template.c (M_DECL_FUNC (__fmin)): Likewise.
+
 	* bits/long-double.h: New file.
 	* sysdeps/ieee754/ldbl-128/bits/long-double.h: Likewise.
 	* sysdeps/ieee754/ldbl-96/bits/long-double.h: Likewise.
diff --git a/math/s_fmax_template.c b/math/s_fmax_template.c
index dea53d45f0..e855b724bc 100644
--- a/math/s_fmax_template.c
+++ b/math/s_fmax_template.c
@@ -22,7 +22,14 @@
 FLOAT
 M_DECL_FUNC (__fmax) (FLOAT x, FLOAT y)
 {
-  return (isgreaterequal (x, y) || isnan (y)) ? x : y;
+  if (isgreaterequal (x, y))
+    return x;
+  else if (isless (x, y))
+    return y;
+  else if (issignaling (x) || issignaling (y))
+    return x + y;
+  else
+    return isnan (y) ? x : y;
 }
 
 declare_mgen_alias (__fmax, fmax);
diff --git a/math/s_fmin_template.c b/math/s_fmin_template.c
index b70989ac74..82009bb7e8 100644
--- a/math/s_fmin_template.c
+++ b/math/s_fmin_template.c
@@ -23,7 +23,14 @@
 FLOAT
 M_DECL_FUNC (__fmin) (FLOAT x, FLOAT y)
 {
-  return (islessequal (x, y) || isnan (y)) ? x : y;
+  if (islessequal (x, y))
+    return x;
+  else if (isgreater (x, y))
+    return y;
+  else if (issignaling (x) || issignaling (y))
+    return x + y;
+  else
+    return isnan (y) ? x : y;
 }
 declare_mgen_alias (__fmin, fmin);