new file mode 100644
--- /dev/null
+++ b/m4/check-math-lib.m4
@@ -0,0 +1,32 @@
+# check-math-lib.m4 serial 1
+dnl Copyright (C) 2007 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+dnl
+dnl AC_CHECK_MATH_LIB (VARIABLE, EXPRESSION)
+dnl
+dnl Checks whether EXPRESSION requires -lm to compile and link.  If so, sets
+dnl the shell VARIABLE to -lm, otherwise to the empty string.
+dnl
+dnl Example: AC_CHECK_MATH_LIB([ROUNDF_LIBM], [x = roundf (x);])
+AC_DEFUN([gl_CHECK_MATH_LIB], [
+  save_LIBS=$LIBS
+  $1=?
+  for libm in "" "-lm"; do
+    LIBS="$save_LIBS $libm"
+    AC_TRY_LINK([
+       #ifndef __NO_MATH_INLINES
+       # define __NO_MATH_INLINES 1 /* for glibc */
+       #endif
+       #include <math.h>
+       double x;],
+      [$2],
+      [$1=$libm
+break])
+  done
+  LIBS=$save_LIBS
+  if test "$$1" = "?"; then
+    $1=
+  fi
+])