Fix compiler warnings (signed / unsigned mismatch)

clang warnings:

    src/ccutil/unicharcompress.cpp:172:27: warning: comparison of integers of different signs: 'int' and 'std::__cxx1998::vector::size_type' (aka 'unsigned long') [-Wsign-compare]
    src/lstm/recodebeam.cpp:129:29: warning: comparison of integers of different signs: 'std::__cxx1998::vector::size_type' (aka 'unsigned long') and 'int' [-Wsign-compare]
    src/lstm/recodebeam.cpp:276:48: warning: comparison of integers of different signs: 'std::__cxx1998::vector::size_type' (aka 'unsigned long') and 'int' [-Wsign-compare]
    unittest/imagedata_test.cc:101:21: warning: comparison of integers of different signs: 'int' and 'std::__cxx1998::vector::size_type' (aka 'unsigned long') [-Wsign-compare]
    unittest/linlsq_test.cc:33:23: warning: comparison of integers of different signs: 'int' and 'std::__cxx1998::vector::size_type' (aka 'unsigned long') [-Wsign-compare]
    unittest/linlsq_test.cc:44:23: warning: comparison of integers of different signs: 'int' and 'std::__cxx1998::vector::size_type' (aka 'unsigned long') [-Wsign-compare]
    unittest/nthitem_test.cc:27:23: warning: comparison of integers of different signs: 'int' and 'unsigned long' [-Wsign-compare]
    unittest/nthitem_test.cc:68:21: warning: comparison of integers of different signs: 'int' and 'unsigned long' [-Wsign-compare]
    unittest/stats_test.cc:26:23: warning: comparison of integers of different signs: 'int' and 'unsigned long' [-Wsign-compare]

Signed-off-by: Stefan Weil <sw@weilnetz.de>

Author: stweil

src/ccutil/unicharcompress.cpp

@@ -4,7 +4,6 @@
 //              place of a single large code for CJK, similarly for Indic,
 //              and dissection of ligatures for other scripts.
 // Author:      Ray Smith
-// Created:     Wed Mar 04 14:45:01 PST 2015
 //
 // (C) Copyright 2015, Google Inc.
 // Licensed under the Apache License, Version 2.0 (the "License");
@@ -169,7 +168,7 @@ bool UnicharCompress::ComputeEncoding(const UNICHARSET& unicharset, int null_id,
       } else {
         // Add the direct_set unichar-ids of the unicodes in sequence to the
         // code.
-        for (int i = 0; i < unicodes.size(); ++i) {
+        for (size_t i = 0; i < unicodes.size(); ++i) {
           int position = code.length();
           if (position >= RecodedCharID::kMaxCodeLen) {
             tprintf("Unichar %d=%s is too long to encode!!\n", u,

src/lstm/recodebeam.cpp

@@ -112,7 +112,6 @@ void RecodeBeamSearch::SaveMostCertainChoices(const float* outputs,
                                              const UNICHARSET* charset,
                                              int xCoord) {
   std::vector<std::pair<const char*, float>> choices;
-  int pos = 0;
   for (int i = 0; i < num_outputs; ++i) {
     if (outputs[i] >= 0.01f) {
       const char* character;
@@ -123,7 +122,7 @@ void RecodeBeamSearch::SaveMostCertainChoices(const float* outputs,
       } else {
         character = charset->id_to_unichar_ext(i);
       }
-      pos = 0;
+      size_t pos = 0;
       //order the possible choices within one timestep
       //beginning with the most likely
       while (choices.size() > pos && choices[pos].second > outputs[i]) {
@@ -267,12 +266,11 @@ void RecodeBeamSearch::ExtractBestPathAsWords(const TBOX& line_box,
             summed_propabilities[it->first] += it->second;
           }
           std::vector<std::pair<const char*, float>> accumulated_timestep;
-          int pos;
           for (auto it = summed_propabilities.begin();
                it != summed_propabilities.end(); ++it) {
             if(sum == 0) break;
             it->second/=sum;
-            pos = 0;
+            size_t pos = 0;
             while (accumulated_timestep.size() > pos
                    && accumulated_timestep[pos].second > it->second) {
               pos++;

unittest/imagedata_test.cc

@@ -32,7 +32,7 @@ class ImagedataTest : public ::testing::Test {
   ImagedataTest() {}
 
   // Creates a fake DocumentData, writes it to a file, and returns the filename.
-  std::string MakeFakeDoc(int num_pages, int doc_id,
+  std::string MakeFakeDoc(int num_pages, unsigned doc_id,
                      std::vector<std::string>* page_texts) {
     // The size of the fake images that we will use.
     const int kImageSize = 1048576;
@@ -43,7 +43,7 @@ class ImagedataTest : public ::testing::Test {
     for (int p = 0; p < num_pages; ++p) {
       // Make some fake text that is different for each page and save it.
       page_texts->push_back(
-          absl::StrFormat("Page %d of %d in doc %d", p, num_pages, doc_id));
+          absl::StrFormat("Page %d of %d in doc %u", p, num_pages, doc_id));
       // Make an imagedata and put it in the document.
       ImageData* imagedata =
           ImageData::Build("noname", p, "eng", fake_image.data(),
@@ -98,7 +98,7 @@ TEST_F(ImagedataTest, CachesMultiDocs) {
   const std::vector<int> kNumPages = {6, 5, 7};
   std::vector<std::vector<std::string>> page_texts;
   GenericVector<STRING> filenames;
-  for (int d = 0; d < kNumPages.size(); ++d) {
+  for (size_t d = 0; d < kNumPages.size(); ++d) {
     page_texts.emplace_back(std::vector<std::string>());
     std::string filename = MakeFakeDoc(kNumPages[d], d, &page_texts.back());
     filenames.push_back(STRING(filename.c_str()));

unittest/linlsq_test.cc

@@ -30,7 +30,7 @@ class LLSQTest : public testing::Test {
   }
   FCOORD PtsMean(const std::vector<FCOORD>& pts) {
     FCOORD total(0, 0);
-    for (int i = 0; i < pts.size(); i++) {
+    for (size_t i = 0; i < pts.size(); i++) {
       total += pts[i];
     }
     return (pts.size() > 0) ? total / pts.size() : total;
@@ -41,7 +41,7 @@ class LLSQTest : public testing::Test {
     FCOORD nvec = !orth;
     nvec.normalise();
     double expected_answer = 0;
-    for (int i = 0; i < pts.size(); i++) {
+    for (size_t i = 0; i < pts.size(); i++) {
       llsq.add(pts[i].x(), pts[i].y());
       double dot = nvec % (pts[i] - xavg);
       expected_answer += dot * dot;

unittest/nthitem_test.cc

@@ -24,7 +24,7 @@ class NthItemTest : public testing::Test {
   virtual ~NthItemTest();
   // Pushes the test data onto the KDVector.
   void PushTestData(KDVector* v) {
-    for (int i = 0; i < ARRAYSIZE(test_data); ++i) {
+    for (size_t i = 0; i < ARRAYSIZE(test_data); ++i) {
       IntKDPair pair(test_data[i], i);
       v->push_back(pair);
     }
@@ -65,7 +65,7 @@ TEST_F(NthItemTest, BoringTest) {
   KDVector v;
   // Push the test data onto the KDVector.
   int test_data[] = {8, 8, 8, 8, 8, 7, 7, 7, 7};
-  for (int i = 0; i < ARRAYSIZE(test_data); ++i) {
+  for (size_t i = 0; i < ARRAYSIZE(test_data); ++i) {
     IntKDPair pair(test_data[i], i);
     v.push_back(pair);
   }

unittest/stats_test.cc

@@ -23,7 +23,7 @@ class STATSTest : public testing::Test {
  public:
   void SetUp() {
     stats_.set_range(0, 16);
-    for (int i = 0; i < ARRAYSIZE(kTestData); ++i)
+    for (size_t i = 0; i < ARRAYSIZE(kTestData); ++i)
       stats_.add(i, kTestData[i]);
   }