diff -r a5f93b21dfe0 configure.ac
--- a/configure.ac	Fri Dec 27 23:01:10 2019 +0300
+++ b/configure.ac	Tue Dec 31 17:58:56 2019 +0100
@@ -3878,6 +3878,11 @@
             SOURCES="$SOURCES $srcdir/src/timer/unix/*.c"
             have_timers=yes
         fi
+        # Set up files for the sensor library
+        AC_DEFINE(SDL_SENSOR_COREMOTION, 1, [ ])
+        SOURCES="$SOURCES $srcdir/src/sensor/coremotion/*.m"
+        have_sensor=yes
+
         # Set up other core UNIX files
         SOURCES="$SOURCES $srcdir/src/core/unix/*.c"
         # The iOS platform requires special setup.