Depends-on:
math
extensions
-float [test $HAVE_DECL_CEILL = 0 || test $REPLACE_CEILL = 1]
+ceil [{ test $HAVE_DECL_CEILL = 0 || test $REPLACE_CEILL = 1; } && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1]
+float [{ test $HAVE_DECL_CEILL = 0 || test $REPLACE_CEILL = 1; } && test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 0]
configure.ac:
gl_FUNC_CEILL