Author: Johannes 'josch' Schauer <josch@debian.org>
Description: On 32bit architectures, parmap will create a segmentation
 https://github.com/rdicosmo/parmap/issues/46
 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=946980

--- a/buildGraph.ml
+++ b/buildGraph.ml
@@ -108,7 +108,7 @@ let graph_helper ?(num_cores=1) availabl
             let srcpkgid = CudfAdd.pkgtoint univ srcpkg in
             (srcpkgid, partitions)
         in
-        let instsets = if num_cores > 1 then
+        let instsets = if Sys.word_size = 64 && num_cores > 1 then
             (* On 32 bit architectures it can happen that the result returned
              * by parmap is too big to fit into the OCaml constraints for
              * maximum allocatable memory. Should this problem occur, we
