diff --git a/glib/gnulib/signbitd.c b/glib/gnulib/signbitd.c
index 7b20f9b2c..dfc1c9092 100644
--- a/glib/gnulib/signbitd.c
+++ b/glib/gnulib/signbitd.c
@@ -17,7 +17,7 @@
 #include <config.h>
 
 /* Specification.  */
-#include <math.h>
+#include <gnulib_math.h>
 
 #include <string.h>
 #include "isnand-nolibm.h"
diff --git a/glib/gnulib/signbitf.c b/glib/gnulib/signbitf.c
index 57e6ef4c7..573d6d975 100644
--- a/glib/gnulib/signbitf.c
+++ b/glib/gnulib/signbitf.c
@@ -17,7 +17,7 @@
 #include <config.h>
 
 /* Specification.  */
-#include <math.h>
+#include <gnulib_math.h>
 
 #include <string.h>
 #include "isnanf-nolibm.h"
diff --git a/glib/gnulib/signbitl.c b/glib/gnulib/signbitl.c
index b1714aadc..11b3e66c9 100644
--- a/glib/gnulib/signbitl.c
+++ b/glib/gnulib/signbitl.c
@@ -17,7 +17,7 @@
 #include <config.h>
 
 /* Specification.  */
-#include <math.h>
+#include <gnulib_math.h>
 
 #include <string.h>
 #include "isnanl-nolibm.h"