--- configure.ac.orig	2020-11-26 23:20:59 UTC
+++ configure.ac
@@ -842,7 +842,7 @@ save_LIBS="$LIBS"
 AM_CONDITIONAL(BUILD_SPHINX, test "x$have_glib" = "xyes" -a "x$have_windows" = "xno" -a "x$have_png" = "xyes")
 
 save_LIBS="$LIBS"
-AC_CHECK_LIB(rt, shm_open, shm_LIBS="-lrt")
+AC_CHECK_LIB(c, shm_open, shm_LIBS="")
 AC_SUBST(shm_LIBS)
 LIBS="$save_LIBS"