ng_corpus_generator: restore use of boost::next()

libc++ checks for forward_iterator_tag in std::next(), which isn't
provided by our (Boost-derived) ue2_graph iterators.

diff --git a/util/ng_corpus_generator.cpp b/util/ng_corpus_generator.cpp
index f2e8f7f9456d3e16fc160f884025165823968b50..72c13e84e0ab8d2e3d0b451cf6e8be597d5e3518 100644 (file)
--- a/util/ng_corpus_generator.cpp
+++ b/util/ng_corpus_generator.cpp
@@ -53,6 +53,8 @@
 #include <sstream>
 #include <vector>
 
+#include <boost/utility.hpp>
+
 using namespace std;
 using namespace ue2;
 
@@ -194,7 +196,7 @@ void findPaths(const NGHolder &g, CorpusProperties &cProps,
             // If we've got no further adjacent vertices, re-use p rather than
             // copying it for the next path.
             unique_ptr<VertexPath> new_path;
-            if (std::next(ai) == ae) {
+            if (boost::next(ai) == ae) {
                 new_path = std::move(p);
             } else {
                 new_path = make_unique<VertexPath>(*p);