diff --git a/src/parser.n/classifier.cpp b/src/parser.n/classifier.cpp
index 34f9cc2ab..21e062a61 100644
--- a/src/parser.n/classifier.cpp
+++ b/src/parser.n/classifier.cpp
@@ -279,8 +279,8 @@ void NeuralNetworkClassifier::compute_gradient(
 
     /*arma::uvec classes_mask = arma::find(Y >= 0);*/
     Eigen::VectorXd __ = (Y.array() >= 0).select(
-        Eigen::VectorXd::Ones(hidden_layer_size),
-        Eigen::VectorXd::Zero(hidden_layer_size));
+        Eigen::VectorXd::Ones(nr_classes),
+        Eigen::VectorXd::Zero(nr_classes));
     double best = output(opt_class);
     output = __.asDiagonal() * Eigen::VectorXd((output.array() - best).exp());
     double sum1 = output(correct_class);
diff --git a/src/parser.n/parser_frontend.cpp b/src/parser.n/parser_frontend.cpp
index 935f9873d..f99ec64c2 100644
--- a/src/parser.n/parser_frontend.cpp
+++ b/src/parser.n/parser_frontend.cpp
@@ -506,7 +506,9 @@ void NeuralNetworkParserFrontend::test(void) {
   size_t corr_heads = 0, corr_deprels = 0, nr_tokens = 0;
 
   timer t;
-  while (inst = reader.next()) {
+  while (true) {
+    inst = reader.next();
+    if (inst == NULL) { break; }
     predict((*inst), heads, deprels);
     writer.write(*inst, heads, deprels);
 
diff --git a/src/utils/smartmap.hpp b/src/utils/smartmap.hpp
index b0123e33c..3f15fc550 100644
--- a/src/utils/smartmap.hpp
+++ b/src/utils/smartmap.hpp
@@ -648,7 +648,7 @@ class IndexableSmartMap : public SmartMap<int32_t> {
    *  @return   const char *  pointer to the key
    */
   const char* at(const size_t& i) const {
-    if (i >= 0 && i < _num_entries) {
+    if (i < _num_entries) {
       return SmartMap<int32_t>::_key_buffer + entries[i];
     } else {
       return 0;
diff --git a/src/utils/strutils.hpp b/src/utils/strutils.hpp
index dd78a6302..8c485c08b 100644
--- a/src/utils/strutils.hpp
+++ b/src/utils/strutils.hpp
@@ -16,7 +16,7 @@ inline void trim(std::string& str) {
   size_t len = str.size();
   if (len == 0) { return; }
 
-  while (len -1 >=0 && (str[len-1] == ' '
+  while (len >= 1 && (str[len-1] == ' '
         || str[len-1]=='\t'
         || str[len-1] == '\r'
         || str[len-1] == '\n')) {