diff --git a/m4/slibtool.m4 b/m4/slibtool.m4
index 0ec5f66..d2dd266 100644
--- a/m4/slibtool.m4
+++ b/m4/slibtool.m4
@@ -530,9 +530,6 @@ m4_if([$1],[Fortran 77],[
 # slibtool: SLIBTOOL_LANG(Fortran 77)
 AC_PROG_FC
 AC_PROG_F77
-
-SLIBTOOL_LFLAG_LIBM
-SLIBTOOL_LFLAG_LTDL
 ])
 ])
 
@@ -560,9 +557,6 @@ AC_REQUIRE([AC_PROG_RANLIB])
 AC_REQUIRE([AC_PROG_LN_S])
 AC_REQUIRE([AC_PROG_MKDIR_P])
 
-AC_REQUIRE([SLIBTOOL_LFLAG_LIBM])
-AC_REQUIRE([SLIBTOOL_LFLAG_LTDL])
-
 AC_PROG_AWK
 AC_PROG_LEX
 AC_PROG_SED