Merge remote-tracking branch 'upstream/master'

16 files changed, 169 insertions, 173 deletions

diff --git a/decoder/bottom_up_parser.cc b/decoder/bottom_up_parser.cc
index 63939221..ed79aaf0 100644
--- a/decoder/bottom_up_parser.cc
+++ b/decoder/bottom_up_parser.cc
@@ -84,7 +84,7 @@ class ActiveChart {
       const GrammarIter* ni = gptr_->Extend(symbol);
       if (!ni) return;
       Hypergraph::TailNodeVector na(ant_nodes_.size() + 1);
-      for (int i = 0; i < ant_nodes_.size(); ++i)
+      for (unsigned i = 0; i < ant_nodes_.size(); ++i)
         na[i] = ant_nodes_[i];
       na[ant_nodes_.size()] = node_index;
       out_cell->push_back(ActiveItem(ni, na, lattice_cost));
@@ -154,7 +154,7 @@ PassiveChart::PassiveChart(const string& goal,
     goal_idx_(-1),
     lc_fid_(FD::Convert("LatticeCost")) {
   act_chart_.resize(grammars_.size());
-  for (int i = 0; i < grammars_.size(); ++i)
+  for (unsigned i = 0; i < grammars_.size(); ++i)
     act_chart_[i] = new ActiveChart(forest, *this);
   if (!kGOAL) kGOAL = TD::Convert("Goal") * -1;
   if (!SILENT) cerr << "  Goal category: [" << goal << ']' << endl;
@@ -204,12 +204,12 @@ void PassiveChart::ApplyRules(const int i,
 
 void PassiveChart::ApplyUnaryRules(const int i, const int j) {
   const vector<int>& nodes = chart_(i,j);  // reference is important!
-  for (int gi = 0; gi < grammars_.size(); ++gi) {
+  for (unsigned gi = 0; gi < grammars_.size(); ++gi) {
     if (!grammars_[gi]->HasRuleForSpan(i,j,input_.Distance(i,j))) continue;
-    for (int di = 0; di < nodes.size(); ++di) {
+    for (unsigned di = 0; di < nodes.size(); ++di) {
       const WordID& cat = forest_->nodes_[nodes[di]].cat_;
       const vector<TRulePtr>& unaries = grammars_[gi]->GetUnaryRulesForRHS(cat);
-      for (int ri = 0; ri < unaries.size(); ++ri) {
+      for (unsigned ri = 0; ri < unaries.size(); ++ri) {
         // cerr << "At (" << i << "," << j << "): applying " << unaries[ri]->AsString() << endl;
         const Hypergraph::TailNodeVector ant(1, nodes[di]);
         ApplyRule(i, j, unaries[ri], ant, 0);  // may update nodes
@@ -224,15 +224,15 @@ bool PassiveChart::Parse() {
   size_t res = min(static_cast<size_t>(2000000), static_cast<size_t>(in_size_2 * 1000));
   forest_->edges_.reserve(res);
   goal_idx_ = -1;
-  for (int gi = 0; gi < grammars_.size(); ++gi)
+  for (unsigned gi = 0; gi < grammars_.size(); ++gi)
     act_chart_[gi]->SeedActiveChart(*grammars_[gi]);
 
   if (!SILENT) cerr << "    ";
-  for (int l=1; l<input_.size()+1; ++l) {
+  for (unsigned l=1; l<input_.size()+1; ++l) {
     if (!SILENT) cerr << '.';
-    for (int i=0; i<input_.size() + 1 - l; ++i) {
-      int j = i + l;
-      for (int gi = 0; gi < grammars_.size(); ++gi) {
+    for (unsigned i=0; i<input_.size() + 1 - l; ++i) {
+      unsigned j = i + l;
+      for (unsigned gi = 0; gi < grammars_.size(); ++gi) {
         const Grammar& g = *grammars_[gi];
         if (g.HasRuleForSpan(i, j, input_.Distance(i, j))) {
           act_chart_[gi]->AdvanceDotsForAllItemsInCell(i, j, input_);
@@ -248,7 +248,7 @@ bool PassiveChart::Parse() {
       }
       ApplyUnaryRules(i,j);
 
-      for (int gi = 0; gi < grammars_.size(); ++gi) {
+      for (unsigned gi = 0; gi < grammars_.size(); ++gi) {
         const Grammar& g = *grammars_[gi];
           // deal with non-terminals that were just proved
           if (g.HasRuleForSpan(i, j, input_.Distance(i,j)))
@@ -256,7 +256,7 @@ bool PassiveChart::Parse() {
       }
     }
     const vector<int>& dh = chart_(0, input_.size());
-    for (int di = 0; di < dh.size(); ++di) {
+    for (unsigned di = 0; di < dh.size(); ++di) {
       const Hypergraph::Node& node = forest_->nodes_[dh[di]];
       if (node.cat_ == goal_cat_) {
         Hypergraph::TailNodeVector ant(1, node.id_);
@@ -272,7 +272,7 @@ bool PassiveChart::Parse() {
 }
 
 PassiveChart::~PassiveChart() {
-  for (int i = 0; i < act_chart_.size(); ++i)
+  for (unsigned i = 0; i < act_chart_.size(); ++i)
     delete act_chart_[i];
 }
 
diff --git a/decoder/cfg.cc b/decoder/cfg.cc
index cd7e66e9..d6ee651a 100644
--- a/decoder/cfg.cc
+++ b/decoder/cfg.cc
@@ -229,13 +229,13 @@ template <>
 struct null_for<RHS> {
   static RHS null;
 };
-*/
 
 template <>
-BinRhs null_traits<BinRhs>::null(std::numeric_limits<int>::min(),std::numeric_limits<int>::min());
+BinRhs null_traits<BinRhs>::xnull(std::numeric_limits<int>::min(),std::numeric_limits<int>::min());
 
 template <>
-RHS null_traits<RHS>::null(1,std::numeric_limits<int>::min());
+RHS null_traits<RHS>::xnull(1,std::numeric_limits<int>::min());
+*/
 
 template <class Rhs>
 struct add_virtual_rules {
@@ -250,7 +250,7 @@ struct add_virtual_rules {
   R2L rhs2lhs; // an rhs maps to this -virtntid, or original id if length 1
   bool name_nts;
   add_virtual_rules(CFG &cfg,bool name_nts=false) : nts(cfg.nts),rules(cfg.rules),newnt(-nts.size()),newruleid(rules.size()),name_nts(name_nts) {
-    HASH_MAP_EMPTY(rhs2lhs,null_traits<Rhs>::null);
+    HASH_MAP_EMPTY(rhs2lhs,null_traits<Rhs>::xnull);
   }
   NTHandle get_virt(Rhs const& r) {
     NTHandle nt=get_default(rhs2lhs,r,newnt);
diff --git a/decoder/ff_bleu.h b/decoder/ff_bleu.h
index e93731c3..5544920e 100644
--- a/decoder/ff_bleu.h
+++ b/decoder/ff_bleu.h
@@ -6,7 +6,6 @@
 
 #include "hg.h"
 #include "ff.h"
-#include "config.h"
 
 class BLEUModelImpl;
 
diff --git a/decoder/ff_dwarf.cc b/decoder/ff_dwarf.cc
index 3daa85ac..43528405 100644
--- a/decoder/ff_dwarf.cc
+++ b/decoder/ff_dwarf.cc
@@ -519,7 +519,7 @@ void Dwarf::neighboringFWs(const Lattice& l, const int& i, const int& j, const m
   while (idx>=0) {
     if (l[idx].size()>0) { 
       if (fw_hash.find(l[idx][0].label)!=fw_hash.end()) {
-        *lfw++;  
+        lfw++;  
       }
     }
     idx-=l[idx][0].dist2next;
@@ -528,7 +528,7 @@ void Dwarf::neighboringFWs(const Lattice& l, const int& i, const int& j, const m
   while (idx<l.size()) {
     if (l[idx].size()>0) { 
       if (fw_hash.find(l[idx][0].label)!=fw_hash.end()) {
-        *rfw++;
+        rfw++;
       }
     }
     idx+=l[idx][0].dist2next;
@@ -787,7 +787,7 @@ bool Dwarf::generalizeOrientation(CountTable* table, const std::map<WordID,WordI
       }
     }
   }
-
+  return false; // no idea if this is right
 }
  
 
diff --git a/decoder/ff_klm.cc b/decoder/ff_klm.cc
index a4b26f7c..7a84add7 100644
--- a/decoder/ff_klm.cc
+++ b/decoder/ff_klm.cc
@@ -373,15 +373,17 @@ boost::shared_ptr<FeatureFunction> KLanguageModelFactory::Create(std::string par
   if (!RecognizeBinary(filename.c_str(), m)) m = HASH_PROBING;
 
   switch (m) {
-    case HASH_PROBING:
+    case PROBING:
       return CreateModel<ProbingModel>(param);
-    case TRIE_SORTED:
+    case REST_PROBING:
+      return CreateModel<RestProbingModel>(param);
+    case TRIE:
       return CreateModel<TrieModel>(param);
-    case ARRAY_TRIE_SORTED:
+    case ARRAY_TRIE:
       return CreateModel<ArrayTrieModel>(param);
-    case QUANT_TRIE_SORTED:
+    case QUANT_TRIE:
       return CreateModel<QuantTrieModel>(param);
-    case QUANT_ARRAY_TRIE_SORTED:
+    case QUANT_ARRAY_TRIE:
       return CreateModel<QuantArrayTrieModel>(param);
     default:
       UTIL_THROW(util::Exception, "Unrecognized kenlm binary file type " << (unsigned)m);
diff --git a/decoder/ff_lm.h b/decoder/ff_lm.h
index 8885efce..ccee4268 100644
--- a/decoder/ff_lm.h
+++ b/decoder/ff_lm.h
@@ -6,7 +6,9 @@
 
 #include "hg.h"
 #include "ff.h"
+#ifdef HAVE_CONFIG_H
 #include "config.h"
+#endif
 
 // everything in this file is deprecated and may be broken.
 // Chris Dyer, Mar 2011
diff --git a/decoder/hg.cc b/decoder/hg.cc
index 180986d7..0dcbe91f 100644
--- a/decoder/hg.cc
+++ b/decoder/hg.cc
@@ -56,7 +56,7 @@ struct less_ve {
 
 Hypergraph::Edge const* Hypergraph::ViterbiSortInEdges(EdgeProbs const& ev)
 {
-  for (int i=0;i<nodes_.size();++i) {
+  for (unsigned i=0;i<nodes_.size();++i) {
     EdgesVector &ie=nodes_[i].in_edges_;
     std::sort(ie.begin(),ie.end(),less_ve(ev));
   }
@@ -70,9 +70,9 @@ prob_t Hypergraph::ComputeEdgeViterbi(EdgeProbs *ev) const {
 }
 
 prob_t Hypergraph::ComputeEdgeViterbi(NodeProbs const& nv,EdgeProbs *ev) const {
-  int ne=edges_.size();
+  unsigned ne=edges_.size();
   ev->resize(ne);
-  for (int i=0;i<ne;++i) {
+  for (unsigned i=0;i<ne;++i) {
     Edge const& e=edges_[i];
     prob_t r=e.edge_prob_;
     TailNodeVector const& t=e.tail_nodes_;
@@ -162,7 +162,7 @@ prob_t Hypergraph::ComputeEdgePosteriors(double scale, vector<prob_t>* posts) co
                   SparseVector<prob_t>,
                   ScaledTransitionEventWeightFunction>(*this, &pv, weight, w2);
   posts->resize(edges_.size());
-  for (int i = 0; i < edges_.size(); ++i)
+  for (unsigned i = 0; i < edges_.size(); ++i)
     (*posts)[i] = prob_t(pv.value(i));
   return inside;
 }
@@ -175,7 +175,7 @@ prob_t Hypergraph::ComputeBestPathThroughEdges(vector<prob_t>* post) const {
                   SparseVector<TropicalValue>,
                   ViterbiTransitionEventWeightFunction>(*this, &pv);
   post->resize(edges_.size());
-  for (int i = 0; i < edges_.size(); ++i)
+  for (unsigned i = 0; i < edges_.size(); ++i)
     (*post)[i] = pv.value(i).v_;
   return viterbi_weight.v_;
 }
@@ -183,12 +183,12 @@ prob_t Hypergraph::ComputeBestPathThroughEdges(vector<prob_t>* post) const {
 void Hypergraph::PushWeightsToSource(double scale) {
   vector<prob_t> posts;
   ComputeEdgePosteriors(scale, &posts);
-  for (int i = 0; i < nodes_.size(); ++i) {
+  for (unsigned i = 0; i < nodes_.size(); ++i) {
     const Hypergraph::Node& node = nodes_[i];
     prob_t z = prob_t::Zero();
-    for (int j = 0; j < node.out_edges_.size(); ++j)
+    for (unsigned j = 0; j < node.out_edges_.size(); ++j)
       z += posts[node.out_edges_[j]];
-    for (int j = 0; j < node.out_edges_.size(); ++j) {
+    for (unsigned j = 0; j < node.out_edges_.size(); ++j) {
       edges_[node.out_edges_[j]].edge_prob_ = posts[node.out_edges_[j]] / z;
     }
   }
@@ -201,7 +201,7 @@ struct vpusher : public vector<TropicalValue> {
   void operator()(int n,int /*ei*/,Hypergraph::Edge &e) const {
     Hypergraph::TailNodeVector const& t=e.tail_nodes_;
     prob_t p=e.edge_prob_;
-    for (int i=0;i<t.size();++i)
+    for (unsigned i=0;i<t.size();++i)
       p*=(*this)[t[i]].v_;
     e.feature_values_.set_value(fid,log(e.edge_prob_=p/(*this)[n].v_));
   }
@@ -229,12 +229,12 @@ prob_t Hypergraph::PushViterbiWeightsToGoal(int fid) {
 prob_t Hypergraph::PushWeightsToGoal(double scale) {
   vector<prob_t> posts;
   const prob_t inside_z = ComputeEdgePosteriors(scale, &posts);
-  for (int i = 0; i < nodes_.size(); ++i) {
+  for (unsigned i = 0; i < nodes_.size(); ++i) {
     const Hypergraph::Node& node = nodes_[i];
     prob_t z = prob_t::Zero();
-    for (int j = 0; j < node.in_edges_.size(); ++j)
+    for (unsigned j = 0; j < node.in_edges_.size(); ++j)
       z += posts[node.in_edges_[j]];
-    for (int j = 0; j < node.in_edges_.size(); ++j) {
+    for (unsigned j = 0; j < node.in_edges_.size(); ++j) {
       edges_[node.in_edges_[j]].edge_prob_ = posts[node.in_edges_[j]] / z;
     }
   }
@@ -257,7 +257,7 @@ void Hypergraph::PruneEdges(const EdgeMask& prune_edge, bool run_inside_algorith
   if (run_inside_algorithm) {
     const EdgeExistsWeightFunction wf(prune_edge);
     vector<Boolean> reachable;
-    bool goal_derivable = Inside/* <Boolean, EdgeExistsWeightFunction> */(*this, &reachable, wf);
+    bool goal_derivable = Inside<Boolean, EdgeExistsWeightFunction>(*this, &reachable, wf);
     if (!goal_derivable) {
       edges_.clear();
       nodes_.clear();
@@ -266,11 +266,11 @@ void Hypergraph::PruneEdges(const EdgeMask& prune_edge, bool run_inside_algorith
     }
 
     assert(reachable.size() == nodes_.size());
-    for (int i = 0; i < edges_.size(); ++i) {
+    for (unsigned i = 0; i < edges_.size(); ++i) {
       bool prune = prune_edge[i];
       if (!prune) {
         const Edge& edge = edges_[i];
-        for (int j = 0; j < edge.tail_nodes_.size(); ++j) {
+        for (unsigned j = 0; j < edge.tail_nodes_.size(); ++j) {
           if (!reachable[edge.tail_nodes_[j]]) {
             prune = true;
             break;
@@ -299,7 +299,7 @@ void Hypergraph::MarginPrune(vector<prob_t> const& io,prob_t cutoff,vector<bool>
     cerr<<"Finishing prune for "<<prune.size()<<" edges; CUTOFF=" << cutoff << endl;
   }
   unsigned pc = 0;
-  for (int i = 0; i < io.size(); ++i) {
+  for (unsigned i = 0; i < io.size(); ++i) {
     cutoff*=creep; // start more permissive, then become less generous.  this is barely more than 1.  we want to do this because it's a disaster if something lower in a derivation tree is deleted, but the higher thing remains (unless safe_inside)
     const bool prune_edge = (io[i] < cutoff);
     if (prune_edge) {
@@ -325,11 +325,11 @@ bool Hypergraph::PruneInsideOutside(double alpha,double density,const EdgeMask*
   assert(!use_beam||alpha>0);
   assert(!use_density||density>=1);
   assert(!use_sum_prod_semiring||scale>0);
-  int rnum=edges_.size();
+  unsigned rnum=edges_.size();
   if (use_density) {
     const int plen = ViterbiPathLength(*this);
     vector<WordID> bp;
-    rnum = min(rnum, static_cast<int>(density * static_cast<double>(plen)));
+    rnum = min(rnum, static_cast<unsigned>(density * plen));
     cerr << "Density pruning: keep "<<rnum<<" of "<<edges_.size()<<" edges (viterbi = "<<plen<<" edges)"<<endl;
     if (rnum == edges_.size()) {
       cerr << "No pruning required: denisty already sufficient\n";
@@ -357,7 +357,7 @@ bool Hypergraph::PruneInsideOutside(double alpha,double density,const EdgeMask*
   if (use_beam) {
     prob_t best=prob_t::One();
     if (use_sum_prod_semiring) {
-      for (int i = 0; i < mm.size(); ++i)
+      for (unsigned i = 0; i < mm.size(); ++i)
         if (mm[i] > best) best = mm[i];
     }
     prob_t beam_cut=best*prob_t::exp(-alpha);
@@ -386,10 +386,10 @@ void Hypergraph::PrintGraphviz() const {
          << "\" shape=\"rect\"];\n";
     Hypergraph::TailNodeVector indorder(edge.tail_nodes_.size(), 0);
     int ntc = 0;
-    for (int i = 0; i < edge.rule_->e_.size(); ++i) {
+    for (unsigned i = 0; i < edge.rule_->e_.size(); ++i) {
       if (edge.rule_->e_[i] <= 0) indorder[ntc++] = 1 + (-1 * edge.rule_->e_[i]);
     }
-    for (int i = 0; i < edge.tail_nodes_.size(); ++i) {
+    for (unsigned i = 0; i < edge.tail_nodes_.size(); ++i) {
       cerr << "     " << edge.tail_nodes_[i] << " -> A_" << ei;
       if (edge.tail_nodes_.size() > 1) {
         cerr << " [label=\"" << indorder[i] << "\"]";
@@ -414,8 +414,8 @@ void Hypergraph::PrintGraphviz() const {
 void Hypergraph::Union(const Hypergraph& other) {
   if (&other == this) return;
   if (nodes_.empty()) { nodes_ = other.nodes_; edges_ = other.edges_; return; }
-  int noff = nodes_.size();
-  int eoff = edges_.size();
+  unsigned noff = nodes_.size();
+  unsigned eoff = edges_.size();
   int ogoal = other.nodes_.size() - 1;
   int cgoal = noff - 1;
   // keep a single goal node, so add nodes.size - 1
@@ -428,15 +428,15 @@ void Hypergraph::Union(const Hypergraph& other) {
     Node& cn = nodes_[i + noff];
     cn.id_ = i + noff;
     cn.in_edges_.resize(on.in_edges_.size());
-    for (int j = 0; j < on.in_edges_.size(); ++j)
+    for (unsigned j = 0; j < on.in_edges_.size(); ++j)
       cn.in_edges_[j] = on.in_edges_[j] + eoff;
 
     cn.out_edges_.resize(on.out_edges_.size());
-    for (int j = 0; j < on.out_edges_.size(); ++j)
+    for (unsigned j = 0; j < on.out_edges_.size(); ++j)
       cn.out_edges_[j] = on.out_edges_[j] + eoff;
   }
 
-  for (int i = 0; i < other.edges_.size(); ++i) {
+  for (unsigned i = 0; i < other.edges_.size(); ++i) {
     const Edge& oe = other.edges_[i];
     Edge& ce = edges_[i + eoff];
     ce.id_ = i + eoff;
@@ -449,7 +449,7 @@ void Hypergraph::Union(const Hypergraph& other) {
       ce.head_node_ = oe.head_node_ + noff;
     }
     ce.tail_nodes_.resize(oe.tail_nodes_.size());
-    for (int j = 0; j < oe.tail_nodes_.size(); ++j)
+    for (unsigned j = 0; j < oe.tail_nodes_.size(); ++j)
       ce.tail_nodes_[j] = oe.tail_nodes_[j] + noff;
   }
 
@@ -460,16 +460,6 @@ void Hypergraph::PruneUnreachable(int goal_node_id) {
   TopologicallySortNodesAndEdges(goal_node_id, NULL);
 }
 
-void Hypergraph::RemoveNoncoaccessibleStates(int goal_node_id) {
-  if (goal_node_id < 0) goal_node_id += nodes_.size();
-  assert(goal_node_id >= 0);
-  assert(goal_node_id < nodes_.size());
-
-  // I don't get it: does TopologicallySortNodesAndEdges not remove things that don't connect to goal_index?  it uses goal_index just to order things?  InsideOutside pruning can do this anyway (nearly infinite beam, viterbi semiring)
-  // TODO finish implementation
-  abort();
-}
-
 struct DFSContext {
   int node;
   int edge_iter;
@@ -559,7 +549,7 @@ void Hypergraph::TopologicallySortNodesAndEdges(int goal_index,
   }
 #ifndef HG_EDGES_TOPO_SORTED
   int ec = 0;
-  for (int i = 0; i < reloc_edge.size(); ++i) {
+  for (unsigned i = 0; i < reloc_edge.size(); ++i) {
     int& cp = reloc_edge[i];
     if (cp >= 0) { cp = ec++; }
   }
@@ -576,34 +566,34 @@ void Hypergraph::TopologicallySortNodesAndEdges(int goal_index,
   cerr << endl;
 #endif
   bool no_op = true;
-  for (int i = 0; i < reloc_node.size() && no_op; ++i)
-    if (reloc_node[i] != i) no_op = false;
-  for (int i = 0; i < reloc_edge.size() && no_op; ++i)
-    if (reloc_edge[i] != i) no_op = false;
+  for (unsigned i = 0; i < reloc_node.size() && no_op; ++i)
+    if (reloc_node[i] != static_cast<int>(i)) no_op = false;
+  for (unsigned i = 0; i < reloc_edge.size() && no_op; ++i)
+    if (reloc_edge[i] != static_cast<int>(i)) no_op = false;
   if (no_op) return;
-  for (int i = 0; i < reloc_node.size(); ++i) {
+  for (unsigned i = 0; i < reloc_node.size(); ++i) {
     Node& node = nodes_[i];
     node.id_ = reloc_node[i];
     int c = 0;
-    for (int j = 0; j < node.in_edges_.size(); ++j) {
+    for (unsigned j = 0; j < node.in_edges_.size(); ++j) {
       const int new_index = reloc_edge[node.in_edges_[j]];
       if (new_index >= 0)
         node.in_edges_[c++] = new_index;
     }
     node.in_edges_.resize(c);
     c = 0;
-    for (int j = 0; j < node.out_edges_.size(); ++j) {
+    for (unsigned j = 0; j < node.out_edges_.size(); ++j) {
       const int new_index = reloc_edge[node.out_edges_[j]];
       if (new_index >= 0)
         node.out_edges_[c++] = new_index;
     }
     node.out_edges_.resize(c);
   }
-  for (int i = 0; i < reloc_edge.size(); ++i) {
+  for (unsigned i = 0; i < reloc_edge.size(); ++i) {
     Edge& edge = edges_[i];
     edge.id_ = reloc_edge[i];
     edge.head_node_ = reloc_node[edge.head_node_];
-    for (int j = 0; j < edge.tail_nodes_.size(); ++j)
+    for (unsigned j = 0; j < edge.tail_nodes_.size(); ++j)
       edge.tail_nodes_[j] = reloc_node[edge.tail_nodes_[j]];
   }
   edges_.erase(remove_if(edges_.begin(), edges_.end(), BadId<Edge>()), edges_.end());
@@ -623,7 +613,7 @@ void Hypergraph::EpsilonRemove(WordID eps) {
     kUnaryRule.reset(new TRule("[X] ||| [X,1] ||| [X,1]"));
   }
   vector<bool> kill(edges_.size(), false);
-  for (int i = 0; i < edges_.size(); ++i) {
+  for (unsigned i = 0; i < edges_.size(); ++i) {
     const Edge& edge = edges_[i];
     if (edge.tail_nodes_.empty() &&
         edge.rule_->f_.size() == 1 &&
@@ -637,7 +627,7 @@ void Hypergraph::EpsilonRemove(WordID eps) {
           // same sequence via different paths through the input forest
           // this needs to be investigated and fixed
         } else {
-          for (int j = 0; j < node.out_edges_.size(); ++j)
+          for (unsigned j = 0; j < node.out_edges_.size(); ++j)
             edges_[node.out_edges_[j]].feature_values_ += edge.feature_values_;
           // cerr << "PROMOTED " << edge.feature_values_ << endl;
 	}
@@ -646,19 +636,19 @@ void Hypergraph::EpsilonRemove(WordID eps) {
   }
   bool created_eps = false;
   PruneEdges(kill);
-  for (int i = 0; i < nodes_.size(); ++i) {
+  for (unsigned i = 0; i < nodes_.size(); ++i) {
     const Node& node = nodes_[i];
     if (node.in_edges_.empty()) {
-      for (int j = 0; j < node.out_edges_.size(); ++j) {
+      for (unsigned j = 0; j < node.out_edges_.size(); ++j) {
         Edge& edge = edges_[node.out_edges_[j]];
         if (edge.rule_->Arity() == 2) {
           assert(edge.rule_->f_.size() == 2);
           assert(edge.rule_->e_.size() == 2);
           edge.rule_ = kUnaryRule;
-          int cur = node.id_;
+          unsigned cur = node.id_;
           int t = -1;
           assert(edge.tail_nodes_.size() == 2);
-          for (int i = 0; i < 2; ++i) if (edge.tail_nodes_[i] != cur) { t = edge.tail_nodes_[i]; }
+          for (unsigned i = 0; i < 2u; ++i) if (edge.tail_nodes_[i] != cur) { t = edge.tail_nodes_[i]; }
           assert(t != -1);
           edge.tail_nodes_.resize(1);
           edge.tail_nodes_[0] = t;
@@ -712,14 +702,14 @@ HypergraphP Hypergraph::CreateEdgeSubset(EdgeMask &keep_edges) const {
 HypergraphP Hypergraph::CreateEdgeSubset(EdgeMask &keep_edges,NodeMask &kn) const {
   kn.clear();
   kn.resize(nodes_.size());
-  for (int n=0;n<nodes_.size();++n) { // this nested iteration gives us edges in topo order too
+  for (unsigned n=0;n<nodes_.size();++n) { // this nested iteration gives us edges in topo order too
     EdgesVector const& es=nodes_[n].in_edges_;
-    for (int i=0;i<es.size();++i) {
+    for (unsigned i=0;i<es.size();++i) {
       int ei=es[i];
       if (keep_edges[ei]) {
         const Edge& e = edges_[ei];
         TailNodeVector const& tails=e.tail_nodes_;
-        for (int j=0;j<e.tail_nodes_.size();++j) {
+        for (unsigned j=0;j<e.tail_nodes_.size();++j) {
           if (!kn[tails[j]]) {
             keep_edges[ei]=false;
             goto next_edge;
@@ -738,11 +728,11 @@ HypergraphP Hypergraph::CreateNodeEdgeSubset(NodeMask const& keep_nodes,EdgeMask
   indices_after e2(keep_edges);
   HypergraphP ret(new Hypergraph(n2.n_kept, e2.n_kept, is_linear_chain_));
   Nodes &rn=ret->nodes_;
-  for (int i=0;i<nodes_.size();++i)
+  for (unsigned i=0;i<nodes_.size();++i)
     if (n2.keeping(i))
       rn[n2[i]].copy_reindex(nodes_[i],n2,e2);
   Edges &re=ret->edges_;
-  for (int i=0;i<edges_.size();++i)
+  for (unsigned i=0;i<edges_.size();++i)
     if (e2.keeping(i))
       re[e2[i]].copy_reindex(edges_[i],n2,e2);
   return ret;
@@ -750,11 +740,11 @@ HypergraphP Hypergraph::CreateNodeEdgeSubset(NodeMask const& keep_nodes,EdgeMask
 
 void Hypergraph::TightenEdgeMask(EdgeMask &ke,NodeMask const& kn) const
 {
-  for (int i = 0; i < edges_.size(); ++i) {
+  for (unsigned i = 0; i < edges_.size(); ++i) {
     if (ke[i]) {
       const Edge& edge = edges_[i];
       TailNodeVector const& tails=edge.tail_nodes_;
-      for (int j = 0; j < edge.tail_nodes_.size(); ++j) {
+      for (unsigned j = 0; j < edge.tail_nodes_.size(); ++j) {
         if (!kn[tails[j]]) {
           ke[i]=false;
           goto next_edge;
@@ -766,18 +756,18 @@ void Hypergraph::TightenEdgeMask(EdgeMask &ke,NodeMask const& kn) const
 }
 
 void Hypergraph::set_ids() {
-  for (int i = 0; i < edges_.size(); ++i)
+  for (unsigned i = 0; i < edges_.size(); ++i)
     edges_[i].id_=i;
-  for (int i = 0; i < nodes_.size(); ++i)
+  for (unsigned i = 0; i < nodes_.size(); ++i)
     nodes_[i].id_=i;
 }
 
 void Hypergraph::check_ids() const
 {
-  for (int i = 0; i < edges_.size(); ++i)
-    assert(edges_[i].id_==i);
-  for (int i = 0; i < nodes_.size(); ++i)
-    assert(nodes_[i].id_==i);
+  for (unsigned i = 0; i < edges_.size(); ++i)
+    assert(edges_[i].id_==static_cast<int>(i));
+  for (unsigned i = 0; i < nodes_.size(); ++i)
+    assert(nodes_[i].id_==static_cast<int>(i));
 }
 
 HypergraphP Hypergraph::CreateViterbiHypergraph(const vector<bool>* edges) const {
@@ -796,15 +786,15 @@ HypergraphP Hypergraph::CreateViterbiHypergraph(const vector<bool>* edges) const
   set_ids();
 # endif
   EdgeMask used(edges_.size());
-  for (int i = 0; i < vit_edges.size(); ++i)
+  for (unsigned i = 0; i < vit_edges.size(); ++i)
     used[vit_edges[i]->id_]=true;
   return CreateEdgeSubset(used);
 #else
   map<int, int> old2new_node;
   int num_new_nodes = 0;
-  for (int i = 0; i < vit_edges.size(); ++i) {
+  for (unsigned i = 0; i < vit_edges.size(); ++i) {
     const Edge& edge = *vit_edges[i];
-    for (int j = 0; j < edge.tail_nodes_.size(); ++j) assert(old2new_node.count(edge.tail_nodes_[j]) > 0);
+    for (unsigned j = 0; j < edge.tail_nodes_.size(); ++j) assert(old2new_node.count(edge.tail_nodes_[j]) > 0);
     if (old2new_node.count(edge.head_node_) == 0) {
       old2new_node[edge.head_node_] = num_new_nodes;
       ++num_new_nodes;
@@ -820,7 +810,7 @@ HypergraphP Hypergraph::CreateViterbiHypergraph(const vector<bool>* edges) const
     new_node.id_ = it->second;
   }
 
-  for (int i = 0; i < vit_edges.size(); ++i) {
+  for (unsigned i = 0; i < vit_edges.size(); ++i) {
     const Edge& old_edge = *vit_edges[i];
     Edge& new_edge = out->edges_[i];
     new_edge = old_edge;
@@ -828,7 +818,7 @@ HypergraphP Hypergraph::CreateViterbiHypergraph(const vector<bool>* edges) const
     const int new_head_node = old2new_node[old_edge.head_node_];
     new_edge.head_node_ = new_head_node;
     out->nodes_[new_head_node].in_edges_.push_back(i);
-    for (int j = 0; j < old_edge.tail_nodes_.size(); ++j) {
+    for (unsigned j = 0; j < old_edge.tail_nodes_.size(); ++j) {
       const int new_tail_node = old2new_node[old_edge.tail_nodes_[j]];
       new_edge.tail_nodes_[j] = new_tail_node;
       out->nodes_[new_tail_node].out_edges_.push_back(i);
diff --git a/decoder/hg.h b/decoder/hg.h
index dfa4ac6d..91d25f01 100644
--- a/decoder/hg.h
+++ b/decoder/hg.h
@@ -43,7 +43,7 @@ public:
   Hypergraph() : is_linear_chain_(false) {}
 
   // SmallVector is a fast, small vector<int> implementation for sizes <= 2
-  typedef SmallVectorInt TailNodeVector; // indices in nodes_
+  typedef SmallVectorUnsigned TailNodeVector; // indices in nodes_
   typedef std::vector<int> EdgesVector; // indices in edges_
 
   // TODO get rid of cat_?
@@ -396,7 +396,7 @@ public:
   // (inner product) to set the edge probabilities
   template <class V>
   void Reweight(const V& weights) {
-    for (int i = 0; i < edges_.size(); ++i) {
+    for (unsigned i = 0; i < edges_.size(); ++i) {
       Edge& e = edges_[i];
       e.edge_prob_.logeq(e.feature_values_.dot(weights));
     }
@@ -457,8 +457,6 @@ public:
 
   void PruneUnreachable(int goal_node_id); // DEPRECATED
 
-  void RemoveNoncoaccessibleStates(int goal_node_id = -1);
-
   // remove edges from the hypergraph if prune_edge[edge_id] is true
   // note: if run_inside_algorithm is false, then consumers may be unhappy if you pruned nodes that are built on by nodes that are kept.
   void PruneEdges(const EdgeMask& prune_edge, bool run_inside_algorithm = false);
@@ -524,7 +522,7 @@ public:
 
   template <class V>
   void visit_edges(V &v) {
-    for (int i=0;i<edges_.size();++i)
+    for (unsigned i=0;i<edges_.size();++i)
       v(edges_[i].head_node_,i,edges_[i]);
   }
 
diff --git a/decoder/hg_intersect.cc b/decoder/hg_intersect.cc
index 8752838f..6e3bfee6 100644
--- a/decoder/hg_intersect.cc
+++ b/decoder/hg_intersect.cc
@@ -19,12 +19,12 @@ using namespace std;
 struct RuleFilter {
   unordered_map<vector<WordID>, bool, boost::hash<vector<WordID> > > exists_;
   bool true_lattice;
-  RuleFilter(const Lattice& target, int max_phrase_size) {
+  RuleFilter(const Lattice& target, unsigned max_phrase_size) {
     true_lattice = false;
-    for (int i = 0; i < target.size(); ++i) {
+    for (unsigned i = 0; i < target.size(); ++i) {
       vector<WordID> phrase;
-      int lim = min(static_cast<int>(target.size()), i + max_phrase_size);
-      for (int j = i; j < lim; ++j) {
+      const unsigned lim = min(static_cast<unsigned>(target.size()), i + max_phrase_size);
+      for (unsigned j = i; j < lim; ++j) {
         if (target[j].size() > 1) { true_lattice = true; break; }
         phrase.push_back(target[j][0].label);
         exists_[phrase] = true;
@@ -37,10 +37,10 @@ struct RuleFilter {
     // TODO do some smarter filtering for lattices
     if (true_lattice) return false;  // don't filter "true lattice" input
     const vector<WordID>& e = r.e();
-    for (int i = 0; i < e.size(); ++i) {
+    for (unsigned i = 0; i < e.size(); ++i) {
       if (e[i] <= 0) continue;
       vector<WordID> phrase;
-      for (int j = i; j < e.size(); ++j) {
+      for (unsigned j = i; j < e.size(); ++j) {
         if (e[j] <= 0) break;
         phrase.push_back(e[j]);
         if (exists_.count(phrase) == 0) return true;
@@ -55,7 +55,7 @@ static bool FastLinearIntersect(const Lattice& target, Hypergraph* hg) {
   vector<bool> prune(hg->edges_.size(), false);
   set<int> cov;
   map<const TRule*, TRulePtr> inverted_rules;
-  for (int i = 0; i < prune.size(); ++i) {
+  for (unsigned i = 0; i < prune.size(); ++i) {
     Hypergraph::Edge& edge = hg->edges_[i];
     if (edge.Arity() == 0) {
       const int trg_index = edge.prev_i_;
@@ -87,12 +87,12 @@ bool HG::Intersect(const Lattice& target, Hypergraph* hg) {
 
   vector<bool> rem(hg->edges_.size(), false);
   const RuleFilter filter(target, 15);   // TODO make configurable
-  for (int i = 0; i < rem.size(); ++i)
+  for (unsigned i = 0; i < rem.size(); ++i)
     rem[i] = filter(*hg->edges_[i].rule_);
   hg->PruneEdges(rem, true);
 
-  const int nedges = hg->edges_.size();
-  const int nnodes = hg->nodes_.size();
+  const unsigned nedges = hg->edges_.size();
+  const unsigned nnodes = hg->nodes_.size();
 
   TextGrammar* g = new TextGrammar;
   GrammarPtr gp(g);
@@ -100,7 +100,7 @@ bool HG::Intersect(const Lattice& target, Hypergraph* hg) {
   // each node in the translation forest becomes a "non-terminal" in the new
   // grammar, create the labels here
   const string kSEP = "_";
-  for (int i = 0; i < nnodes; ++i) {
+  for (unsigned i = 0; i < nnodes; ++i) {
     const char* pstr = "CAT";
     if (hg->nodes_[i].cat_ < 0)
       pstr = TD::Convert(-hg->nodes_[i].cat_);
@@ -108,7 +108,7 @@ bool HG::Intersect(const Lattice& target, Hypergraph* hg) {
   }
 
   // construct the grammar
-  for (int i = 0; i < nedges; ++i) {
+  for (unsigned i = 0; i < nedges; ++i) {
     const Hypergraph::Edge& edge = hg->edges_[i];
     const vector<WordID>& tgt = edge.rule_->e();
     const vector<WordID>& src = edge.rule_->f();
@@ -122,7 +122,7 @@ bool HG::Intersect(const Lattice& target, Hypergraph* hg) {
     e.resize(src.size());   // parses using the source side!
     Hypergraph::TailNodeVector tn(edge.tail_nodes_.size());
     int ntc = 0;
-    for (int j = 0; j < tgt.size(); ++j) {
+    for (unsigned j = 0; j < tgt.size(); ++j) {
       const WordID& cur = tgt[j];
       if (cur > 0) {
         f[j] = cur;
@@ -133,7 +133,7 @@ bool HG::Intersect(const Lattice& target, Hypergraph* hg) {
       }
     }
     ntc = 0;
-    for (int j = 0; j < src.size(); ++j) {
+    for (unsigned j = 0; j < src.size(); ++j) {
       const WordID& cur = src[j];
       if (cur > 0) {
         e[j] = cur;
diff --git a/decoder/hg_io.cc b/decoder/hg_io.cc
index 734c2ce8..bfb2fb80 100644
--- a/decoder/hg_io.cc
+++ b/decoder/hg_io.cc
@@ -28,7 +28,7 @@ struct HGReader : public JSONParser {
       hg.ConnectEdgeToHeadNode(&hg.edges_[in_edges[i]], node);
     }
   }
-  void CreateEdge(const TRulePtr& rule, FeatureVector* feats, const SmallVectorInt& tail) {
+  void CreateEdge(const TRulePtr& rule, FeatureVector* feats, const SmallVectorUnsigned& tail) {
     Hypergraph::Edge* edge = hg.AddEdge(rule, tail);
     feats->swap(edge->feature_values_);
     edge->i_ = spans[0];
@@ -229,7 +229,7 @@ struct HGReader : public JSONParser {
   }
   string rp;
   string cat;
-  SmallVectorInt tail;
+  SmallVectorUnsigned tail;
   vector<int> in_edges;
   TRulePtr cur_rule;
   map<int, TRulePtr> rules;
@@ -488,13 +488,13 @@ int getInt(const std::string& in, int &c)
 #define MAX_NODES 100000000
 // parse ('foo', 0.23)
 void ReadPLFEdge(const std::string& in, int &c, int cur_node, Hypergraph* hg) {
-  if (get(in,c++) != '(') { assert(!"PCN/PLF parse error: expected ( at start of cn alt block\n"); }
+  if (get(in,c++) != '(') { cerr << "PCN/PLF parse error: expected (\n"; abort(); }
   vector<WordID> ewords(2, 0);
   ewords[1] = TD::Convert(getEscapedString(in,c));
   TRulePtr r(new TRule(ewords));
   r->ComputeArity();
   // cerr << "RULE: " << r->AsString() << endl;
-  if (get(in,c++) != ',') { cerr << in << endl; assert(!"PCN/PLF parse error: expected , after string\n"); }
+  if (get(in,c++) != ',') { cerr << in << endl; cerr << "PCN/PLF parse error: expected , after string\n"; abort(); }
   size_t cnNext = 1;
   std::vector<float> probs;
   probs.push_back(getFloat(in,c));
@@ -508,10 +508,9 @@ void ReadPLFEdge(const std::string& in, int &c, int cur_node, Hypergraph* hg) {
   if (probs.size()>1) {
     cnNext = static_cast<size_t>(probs.back());
     probs.pop_back();
-    if (cnNext < 1) { cerr << cnNext << endl;
-             assert(!"PCN/PLF parse error: bad link length at last element of cn alt block\n"); }
+    if (cnNext < 1) { cerr << cnNext << endl << "PCN/PLF parse error: bad link length at last element of cn alt block\n"; abort(); }
   }
-  if (get(in,c++) != ')') { assert(!"PCN/PLF parse error: expected ) at end of cn alt block\n"); }
+  if (get(in,c++) != ')') { cerr << "PCN/PLF parse error: expected ) at end of cn alt block\n"; abort(); }
   eatws(in,c);
   Hypergraph::TailNodeVector tail(1, cur_node);
   Hypergraph::Edge* edge = hg->AddEdge(r, tail);
diff --git a/decoder/inside_outside.h b/decoder/inside_outside.h
index dc96f1a9..bb7f9fcc 100644
--- a/decoder/inside_outside.h
+++ b/decoder/inside_outside.h
@@ -31,24 +31,24 @@ template<class WeightType, class WeightFunction>
 WeightType Inside(const Hypergraph& hg,
                   std::vector<WeightType>* result = NULL,
                   const WeightFunction& weight = WeightFunction()) {
-  const int num_nodes = hg.nodes_.size();
+  const unsigned num_nodes = hg.nodes_.size();
   std::vector<WeightType> dummy;
   std::vector<WeightType>& inside_score = result ? *result : dummy;
   inside_score.clear();
   inside_score.resize(num_nodes);
 //  std::fill(inside_score.begin(), inside_score.end(), WeightType()); // clear handles
-  for (int i = 0; i < num_nodes; ++i) {
+  for (unsigned i = 0; i < num_nodes; ++i) {
     WeightType* const cur_node_inside_score = &inside_score[i];
     Hypergraph::EdgesVector const& in=hg.nodes_[i].in_edges_;
-    const int num_in_edges = in.size();
+    const unsigned num_in_edges = in.size();
     if (num_in_edges == 0) {
       *cur_node_inside_score = WeightType(1); //FIXME: why not call weight(edge) instead?
       continue;
     }
-    for (int j = 0; j < num_in_edges; ++j) {
+    for (unsigned j = 0; j < num_in_edges; ++j) {
       const Hypergraph::Edge& edge = hg.edges_[in[j]];
       WeightType score = weight(edge);
-      for (int k = 0; k < edge.tail_nodes_.size(); ++k) {
+      for (unsigned k = 0; k < edge.tail_nodes_.size(); ++k) {
         const int tail_node_index = edge.tail_nodes_[k];
         score *= inside_score[tail_node_index];
       }
@@ -67,7 +67,7 @@ void Outside(const Hypergraph& hg,
   ) {
   assert(result);
   const int num_nodes = hg.nodes_.size();
-  assert(inside_score.size() == num_nodes);
+  assert(static_cast<int>(inside_score.size()) == num_nodes);
   std::vector<WeightType>& outside_score = *result;
   outside_score.clear();
   outside_score.resize(num_nodes);
diff --git a/decoder/kbest.h b/decoder/kbest.h
index 03a8311c..9af3a20e 100644
--- a/decoder/kbest.h
+++ b/decoder/kbest.h
@@ -43,7 +43,7 @@ namespace KBest {
       traverse(tf), w(wf), g(hg), nds(g.nodes_.size()), k_prime(k) {}
 
     ~KBestDerivations() {
-      for (int i = 0; i < freelist.size(); ++i)
+      for (unsigned i = 0; i < freelist.size(); ++i)
         delete freelist[i];
     }
 
@@ -86,7 +86,7 @@ namespace KBest {
 //      Hypergraph::Edge const * operator ->() const { return d->edge; }
     };
 
-    EdgeHandle operator()(int t,int taili,EdgeHandle const& parent) const {
+    EdgeHandle operator()(unsigned t,unsigned taili,EdgeHandle const& parent) const {
       return EdgeHandle(nds[t].D[parent.d->j[taili]]);
     }
 
@@ -98,7 +98,7 @@ namespace KBest {
       size_t operator()(const Derivation* d) const {
         size_t x = 5381;
         x = ((x << 5) + x) ^ d->edge->id_;
-        for (int i = 0; i < d->j.size(); ++i)
+        for (unsigned i = 0; i < d->j.size(); ++i)
           x = ((x << 5) + x) ^ d->j[i];
         return x;
       }
@@ -121,7 +121,7 @@ namespace KBest {
       explicit NodeDerivationState(const DerivationFilter& f = DerivationFilter()) : filter(f) {}
     };
 
-    Derivation* LazyKthBest(int v, int k) {
+    Derivation* LazyKthBest(unsigned v, unsigned k) {
       NodeDerivationState& s = GetCandidates(v);
       CandidateHeap& cand = s.cand;
       DerivationList& D = s.D;
@@ -139,7 +139,7 @@ namespace KBest {
           Derivation* d = cand.back();
           cand.pop_back();
           std::vector<const T*> ants(d->edge->Arity());
-          for (int j = 0; j < ants.size(); ++j)
+          for (unsigned j = 0; j < ants.size(); ++j)
             ants[j] = &LazyKthBest(d->edge->tail_nodes_[j], d->j[j])->yield;
           traverse(*d->edge, ants, &d->yield);
           if (!filter(d->yield)) {
@@ -171,12 +171,12 @@ namespace KBest {
       return freelist.back();
     }
 
-    NodeDerivationState& GetCandidates(int v) {
+    NodeDerivationState& GetCandidates(unsigned v) {
       NodeDerivationState& s = nds[v];
       if (!s.D.empty() || !s.cand.empty()) return s;
 
       const Hypergraph::Node& node = g.nodes_[v];
-      for (int i = 0; i < node.in_edges_.size(); ++i) {
+      for (unsigned i = 0; i < node.in_edges_.size(); ++i) {
         const Hypergraph::Edge& edge = g.edges_[node.in_edges_[i]];
         SmallVectorInt jv(edge.Arity(), 0);
         Derivation* d = CreateDerivation(edge, jv);
@@ -184,7 +184,7 @@ namespace KBest {
         s.cand.push_back(d);
       }
 
-      const int effective_k = std::min(k_prime, s.cand.size());
+      const unsigned effective_k = std::min(k_prime, s.cand.size());
       const typename CandidateHeap::iterator kth = s.cand.begin() + effective_k;
       std::nth_element(s.cand.begin(), kth, s.cand.end(), DerivationCompare());
       s.cand.resize(effective_k);
@@ -194,7 +194,7 @@ namespace KBest {
     }
 
     void LazyNext(const Derivation* d, CandidateHeap* cand, UniqueDerivationSet* ds) {
-      for (int i = 0; i < d->j.size(); ++i) {
+      for (unsigned i = 0; i < d->j.size(); ++i) {
         SmallVectorInt j = d->j;
         ++j[i];
         const Derivation* ant = LazyKthBest(d->edge->tail_nodes_[i], j[i]);
@@ -205,8 +205,12 @@ namespace KBest {
             if (new_d) {
               cand->push_back(new_d);
               std::push_heap(cand->begin(), cand->end(), HeapCompare());
+#ifdef NDEBUG
+              ds->insert(new_d).second;  // insert into uniqueness set
+#else
               bool inserted = ds->insert(new_d).second;  // insert into uniqueness set
               assert(inserted);
+#endif
             }
           }
         }
diff --git a/decoder/maxtrans_blunsom.cc b/decoder/maxtrans_blunsom.cc
index 6efab454..774e4170 100644
--- a/decoder/maxtrans_blunsom.cc
+++ b/decoder/maxtrans_blunsom.cc
@@ -73,7 +73,7 @@ struct Candidate {
     prob_t p = prob_t::One();
     // cerr << "\nEstimating application of " << in_edge.rule_->AsString() << endl;
     vector<const vector<WordID>* > ants(tail.size());
-    for (int i = 0; i < tail.size(); ++i) {
+    for (unsigned i = 0; i < tail.size(); ++i) {
       const Candidate& ant = *D[in_edge.tail_nodes_[i]][j_[i]];
       ants[i] = &ant.state_;
       assert(ant.IsIncorporatedIntoHypergraph());
@@ -99,7 +99,7 @@ ostream& operator<<(ostream& os, const Candidate& cand) {
   else { os << "+LM_node=" << cand.node_index_; }
   os << " edge=" << cand.in_edge_->id_;
   os << " j=<";
-  for (int i = 0; i < cand.j_.size(); ++i)
+  for (unsigned i = 0; i < cand.j_.size(); ++i)
     os << (i==0 ? "" : " ") << cand.j_[i];
   os << "> vit=" << log(cand.inside_prob_);
   os << " est=" << log(cand.est_prob_);
@@ -127,7 +127,7 @@ struct CandidateUniquenessHash {
   size_t operator()(const Candidate* c) const {
     size_t x = 5381;
     x = ((x << 5) + x) ^ c->in_edge_->id_;
-    for (int i = 0; i < c->j_.size(); ++i)
+    for (unsigned i = 0; i < c->j_.size(); ++i)
       x = ((x << 5) + x) ^ c->j_[i];
     return x;
   }
@@ -154,12 +154,12 @@ public:
   }
 
   void Apply() {
-    int num_nodes = in.nodes_.size();
-    int goal_id = num_nodes - 1;
-    int pregoal = goal_id - 1;
+    const unsigned num_nodes = in.nodes_.size();
+    const unsigned goal_id = num_nodes - 1;
+    const unsigned pregoal = goal_id - 1;
     assert(in.nodes_[pregoal].out_edges_.size() == 1);
     cerr << "    ";
-    for (int i = 0; i < in.nodes_.size(); ++i) {
+    for (unsigned i = 0; i < in.nodes_.size(); ++i) {
       cerr << '.';
       KBest(i, i == goal_id);
     }
@@ -174,9 +174,9 @@ public:
 
  private:
   void FreeAll() {
-    for (int i = 0; i < D.size(); ++i) {
+    for (unsigned i = 0; i < D.size(); ++i) {
       CandidateList& D_i = D[i];
-      for (int j = 0; j < D_i.size(); ++j)
+      for (unsigned j = 0; j < D_i.size(); ++j)
         delete D_i[j];
     }
     D.clear();
@@ -216,7 +216,7 @@ public:
     CandidateList freelist;
     cand.reserve(in_edges.size());
     UniqueCandidateSet unique_cands;
-    for (int i = 0; i < in_edges.size(); ++i) {
+    for (unsigned i = 0; i < in_edges.size(); ++i) {
       const Hypergraph::Edge& edge = in.edges_[in_edges[i]];
       const JVector j(edge.tail_nodes_.size(), 0);
       cand.push_back(new Candidate(edge, j, D, is_goal));
@@ -242,20 +242,20 @@ public:
     sort(D_v.begin(), D_v.end(), EstProbSorter());
     // cerr << "  expanded to " << D_v.size() << " nodes\n";
 
-    for (int i = 0; i < cand.size(); ++i)
+    for (unsigned i = 0; i < cand.size(); ++i)
       delete cand[i];
     // freelist is necessary since even after an item merged, it still stays in
     // the unique set so it can't be deleted til now
-    for (int i = 0; i < freelist.size(); ++i)
+    for (unsigned i = 0; i < freelist.size(); ++i)
       delete freelist[i];
   }
 
   void PushSucc(const Candidate& item, const bool is_goal, CandidateHeap* pcand, UniqueCandidateSet* cs) {
     CandidateHeap& cand = *pcand;
-    for (int i = 0; i < item.j_.size(); ++i) {
+    for (unsigned i = 0; i < item.j_.size(); ++i) {
       JVector j = item.j_;
       ++j[i];
-      if (j[i] < D[item.in_edge_->tail_nodes_[i]].size()) {
+      if (static_cast<unsigned>(j[i]) < D[item.in_edge_->tail_nodes_[i]].size()) {
         Candidate query_unique(*item.in_edge_, j);
         if (cs->count(&query_unique) == 0) {
           Candidate* new_cand = new Candidate(*item.in_edge_, j, D, is_goal);
diff --git a/decoder/scfg_translator.cc b/decoder/scfg_translator.cc
index 15abb600..185f979a 100644
--- a/decoder/scfg_translator.cc
+++ b/decoder/scfg_translator.cc
@@ -33,7 +33,7 @@ struct SCFGTranslatorImpl {
   {
     if(conf.count("grammar")){
       vector<string> gfiles = conf["grammar"].as<vector<string> >();
-      for (int i = 0; i < gfiles.size(); ++i) {
+      for (unsigned i = 0; i < gfiles.size(); ++i) {
         if (!SILENT) cerr << "Reading SCFG grammar from " << gfiles[i] << endl;
         TextGrammar* g = new TextGrammar(gfiles[i]);
         g->SetMaxSpan(max_span_limit);
@@ -132,7 +132,7 @@ struct SCFGTranslatorImpl {
       g->SetGrammarName("PassThrough");
       glist.push_back(GrammarPtr(g));
     }
-    for (int gi = 0; gi < glist.size(); ++gi) {
+    for (unsigned gi = 0; gi < glist.size(); ++gi) {
       if(printGrammarsUsed)
         cerr << "Using grammar::" << glist[gi]->GetGrammarName() << endl;
     }
@@ -147,7 +147,7 @@ struct SCFGTranslatorImpl {
     forest->Reweight(weights);
     if (use_ctf_) {
       Hypergraph::Node& goal_node = *(forest->nodes_.end()-1);
-      foreach(int edge_id, goal_node.in_edges_)
+      foreach(unsigned edge_id, goal_node.in_edges_)
         RefineRule(forest->edges_[edge_id].rule_, ctf_iterations_);
       double alpha = ctf_alpha_;
       bool found_parse=false;
@@ -155,7 +155,7 @@ struct SCFGTranslatorImpl {
         cerr << "Coarse-to-fine source parse, alpha=" << alpha << endl;
         found_parse = true;
         Hypergraph refined_forest = *forest;
-        for (int j=0; j < ctf_iterations_; ++j) {
+        for (unsigned j=0; j < ctf_iterations_; ++j) {
           cerr << viterbi_stats(refined_forest,"  Coarse forest",true,show_tree_structure_);
           cerr << "  Iteration " << (j+1) << ": Pruning forest... ";
           refined_forest.BeamPruneInsideOutside(1.0, false, alpha, NULL);
@@ -178,7 +178,7 @@ struct SCFGTranslatorImpl {
       if (!found_parse){
         if (ctf_exhaustive_){
           cerr << "Last resort: refining coarse forest without pruning...";
-          for (int j=0; j < ctf_iterations_; ++j) {
+          for (unsigned j=0; j < ctf_iterations_; ++j) {
             if (RefineForest(forest)){
               cerr << "  Refinement succeeded." << endl;
               forest->Reweight(weights);
@@ -213,7 +213,7 @@ struct SCFGTranslatorImpl {
         Hypergraph::Edge& edge = forest->edges_[edge_id];
         std::vector<int> nt_positions;
         TRulePtr& coarse_rule_ptr = edge.rule_;
-        for(int i=0; i< coarse_rule_ptr->f_.size(); ++i){
+        for(unsigned i=0; i< coarse_rule_ptr->f_.size(); ++i){
           if (coarse_rule_ptr->f_[i] < 0)
             nt_positions.push_back(i);
         }
@@ -225,7 +225,7 @@ struct SCFGTranslatorImpl {
         // fine rules apply only if state splits on tail nodes match fine rule nonterminals
         foreach(TRulePtr& fine_rule_ptr, *(coarse_rule_ptr->fine_rules_)) {
           Hypergraph::TailNodeVector tail;
-          for (int pos_i=0; pos_i<nt_positions.size(); ++pos_i){
+          for (unsigned pos_i=0; pos_i<nt_positions.size(); ++pos_i){
             WordID fine_cat = fine_rule_ptr->f_[nt_positions[pos_i]];
             Split2Node::iterator it =
               s2n.find(StateSplit(edge.tail_nodes_[pos_i], fine_cat));
diff --git a/decoder/trule.cc b/decoder/trule.cc
index 141b8faa..187a003d 100644
--- a/decoder/trule.cc
+++ b/decoder/trule.cc
@@ -18,7 +18,7 @@ bool TRule::IsGoal() const {
 }
 
 static WordID ConvertTrgString(const string& w) {
-  int len = w.size();
+  const unsigned len = w.size();
   WordID id = 0;
   // [X,0] or [0]
   // for target rules, we ignore the category, just keep the index
@@ -33,7 +33,7 @@ static WordID ConvertTrgString(const string& w) {
 }
 
 static WordID ConvertSrcString(const string& w, bool mono = false) {
-  int len = w.size();
+  const unsigned len = w.size();
   // [X,0]
   // for source rules, we keep the category and ignore the index (source rules are
   // always numbered 1, 2, 3...
@@ -60,7 +60,7 @@ static WordID ConvertSrcString(const string& w, bool mono = false) {
 
 static WordID ConvertLHS(const string& w) {
   if (w[0] == '[') {
-    int len = w.size();
+    const unsigned len = w.size();
     if (len < 3) { cerr << "Format error: " << w << endl; exit(1); }
     return TD::Convert(w.substr(1, len-2)) * -1;
   } else {
@@ -100,6 +100,8 @@ namespace {
 // callback for lexer
 int n_assigned=0;
 void assign_trule(const TRulePtr& new_rule, const unsigned int ctf_level, const TRulePtr& coarse_rule, void* extra) {
+  (void) ctf_level;
+  (void) coarse_rule;
   TRule *assignto=(TRule *)extra;
   *assignto=*new_rule;
   ++n_assigned;
@@ -143,15 +145,15 @@ bool TRule::ReadFromString(const string& line, bool strict, bool mono) {
       string ss;
       getline(is, ss);
       //cerr << "L: " << ss << endl;
-      int start = 0;
-      int len = ss.size();
+      unsigned start = 0;
+      unsigned len = ss.size();
       const size_t ppos = ss.find(" |||");
       if (ppos != string::npos) { len = ppos; }
       while (start < len) {
         while(start < len && (ss[start] == ' ' || ss[start] == ';'))
           ++start;
         if (start == len) break;
-        int end = start + 1;
+        unsigned end = start + 1;
         while(end < len && (ss[end] != '=' && ss[end] != ' ' && ss[end] != ';'))
           ++end;
         if (end == len || ss[end] == ' ' || ss[end] == ';') {
@@ -188,7 +190,7 @@ bool TRule::ReadFromString(const string& line, bool strict, bool mono) {
     while(is>>w && w!="|||") { e_.push_back(ConvertTrgString(w)); }
     f_ = e_;
     int x = ConvertLHS("[X]");
-    for (int i = 0; i < f_.size(); ++i)
+    for (unsigned i = 0; i < f_.size(); ++i)
       if (f_[i] <= 0) { f_[i] = x; }
   } else {
     cerr << "F: " << format << endl;
@@ -197,7 +199,7 @@ bool TRule::ReadFromString(const string& line, bool strict, bool mono) {
   if (mono) {
     e_ = f_;
     int ci = 0;
-    for (int i = 0; i < e_.size(); ++i)
+    for (unsigned i = 0; i < e_.size(); ++i)
       if (e_[i] < 0)
         e_[i] = ci--;
   }
@@ -208,7 +210,7 @@ bool TRule::ReadFromString(const string& line, bool strict, bool mono) {
 bool TRule::SanityCheck() const {
   vector<int> used(f_.size(), 0);
   int ac = 0;
-  for (int i = 0; i < e_.size(); ++i) {
+  for (unsigned i = 0; i < e_.size(); ++i) {
     int ind = e_[i];
     if (ind > 0) continue;
     ind = -ind;
@@ -238,7 +240,7 @@ string TRule::AsString(bool verbose) const {
   if (lhs_ && verbose) {
     os << '[' << TD::Convert(lhs_ * -1) << "] |||";
   }
-  for (int i = 0; i < f_.size(); ++i) {
+  for (unsigned i = 0; i < f_.size(); ++i) {
     const WordID& w = f_[i];
     if (w < 0) {
       int wi = w * -1;
@@ -249,7 +251,7 @@ string TRule::AsString(bool verbose) const {
     }
   }
   os << " ||| ";
-  for (int i =0; i<e_.size(); ++i) {
+  for (unsigned i =0; i<e_.size(); ++i) {
     if (i) os << ' ';
     const WordID& w = e_[i];
     if (w < 1)
@@ -261,7 +263,7 @@ string TRule::AsString(bool verbose) const {
     os << " ||| " << scores_;
     if (!a_.empty()) {
       os << " |||";
-      for (int i = 0; i < a_.size(); ++i)
+      for (unsigned i = 0; i < a_.size(); ++i)
         os << ' ' << a_[i];
     }
   }
diff --git a/decoder/trule.h b/decoder/trule.h
index 8eb2a059..6a33d052 100644
--- a/decoder/trule.h
+++ b/decoder/trule.h
@@ -76,7 +76,7 @@ class TRule {
 
   void ESubstitute(const std::vector<const std::vector<WordID>* >& var_values,
                    std::vector<WordID>* result) const {
-    int vc = 0;
+    unsigned vc = 0;
     result->clear();
     for (std::vector<WordID>::const_iterator i = e_.begin(); i != e_.end(); ++i) {
       const WordID& c = *i;
@@ -95,7 +95,7 @@ class TRule {
 
   void FSubstitute(const std::vector<const std::vector<WordID>* >& var_values,
                    std::vector<WordID>* result) const {
-    int vc = 0;
+    unsigned vc = 0;
     result->clear();
     for (std::vector<WordID>::const_iterator i = f_.begin(); i != f_.end(); ++i) {
       const WordID& c = *i;