optionally build zarith.top

Author: Lucas Pluvinage

dune

@@ -8,13 +8,14 @@
    (language c) 
    (names caml_z) 
    (include_dirs (lib gmp)) 
-   (flags "-DHAS_GMP")
+   (flags :standard "-DHAS_GMP")
   )
   (libraries gmp)
   (wrapped false))
 
 (library
  (name zarith_top)
+ (optional)
  (public_name zarith.top)
  (modules zarith_top)
  (libraries zarith compiler-libs.toplevel))