+
+ cf_save_LIBS="$LIBS"
+ LIBS="$LIBS -lm"
+ AC_CACHE_CHECK(if -lm is available for math functions,
+ cf_cv_have_libm,[
+ AC_TRY_LINK([
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <math.h>
+ ],
+ [double x = rand(); printf("result = %g\\n", ]ifelse([$2],,sin(x),$2)[)],
+ [cf_cv_have_libm=yes],
+ [cf_cv_have_libm=no])])
+ LIBS="$cf_save_LIBS"
+
+ if test "$cf_cv_have_libm" = yes
+ then
+ ifelse($1,,[CF_ADD_LIB(m)],[$1=-lm])
+ fi
+else
+ cf_cv_have_libm=yes
+fi
+
+if test "$cf_cv_have_libm" = yes
+then
+ AC_DEFINE(HAVE_MATH_FUNCS,1,[Define to 1 if math functions are available])