diff --git a/src/prtget.cpp b/src/prtget.cpp
index 6095607..c2c7558 100644
--- a/src/prtget.cpp
+++ b/src/prtget.cpp
@@ -926,7 +926,7 @@ void PrtGet::printDiff()
     const map<string, string>& installed = m_pkgDB->installedPackages();
     map<string, string>::const_iterator it = installed.begin();
     const Package* p = 0;
-    int count = 0;
+    size_t count = 0;
     COMP_RESULT result;
     for ( ; it != installed.end(); ++it ) {
 
@@ -1941,28 +1941,28 @@ void PrtGet::remove()
 
 }
 
-void PrtGet::assertMaxArgCount(int count)
+void PrtGet::assertMaxArgCount(size_t count)
 {
     if ( m_parser->otherArgs().size() > count ) {
         argCountFailure(count, "at most");
     }
 }
 
-void PrtGet::assertExactArgCount(int count)
+void PrtGet::assertExactArgCount(size_t count)
 {
     if ( m_parser->otherArgs().size() != count ) {
         argCountFailure(count, "exactly");
     }
 }
 
-void PrtGet::assertMinArgCount(int count)
+void PrtGet::assertMinArgCount(size_t count)
 {
      if ( m_parser->otherArgs().size() < count ) {
          argCountFailure(count, "at least");
      }
 }
 
-void PrtGet::argCountFailure(int count, const string& specifier)
+void PrtGet::argCountFailure(size_t count, const string& specifier)
 {
     cerr << m_appName << " "
          << m_parser->commandName() << " takes " << specifier << " "
diff --git a/src/prtget.h b/src/prtget.h
index 6a82975..8e5ad1f 100644
--- a/src/prtget.h
+++ b/src/prtget.h
@@ -146,10 +146,10 @@ protected:
     static const string DEFAULT_CACHE_FILE;
 
 
-    void assertMinArgCount(int count);
-    void assertMaxArgCount(int count);
-    void assertExactArgCount(int count);
-    void argCountFailure(int count, const string& specifier);
+    void assertMinArgCount(size_t count);
+    void assertMaxArgCount(size_t count);
+    void assertExactArgCount(size_t count);
+    void argCountFailure(size_t count, const string& specifier);
 
     VersionComparator::COMP_RESULT
     compareVersions( const string& v1, const string& v2 );
diff --git a/src/stringhelper.cpp b/src/stringhelper.cpp
index 2b25d3f..2b4f783 100644
--- a/src/stringhelper.cpp
+++ b/src/stringhelper.cpp
@@ -58,18 +58,18 @@ string stripWhiteSpace( const string& s )
         return s;
     }
 
-    int pos = 0;
+    size_t pos = 0;
     string line = s;
-    string::size_type len = line.length();
+    size_t len = line.length();
     while ( pos < len && isspace( line[pos] ) ) {
         ++pos;
     }
     line.erase( 0, pos );
     pos = line.length()-1;
-    while ( pos > -1 && isspace( line[pos] ) ) {
+    while ( pos != (size_t) -1 && isspace( line[pos] ) ) {
         --pos;
     }
-    if ( pos != -1 ) {
+    if ( pos != (size_t) -1 ) {
         line.erase( pos+1 );
     }
     return line;
diff --git a/src/versioncomparator.cpp b/src/versioncomparator.cpp
index 6116a97..b337ddf 100644
--- a/src/versioncomparator.cpp
+++ b/src/versioncomparator.cpp
@@ -39,16 +39,16 @@ COMP_RESULT compareVersions(const string& v1, const string& v2)
 
     tokenizeIntoBlocks(v1, blocks1);
     tokenizeIntoBlocks(v2, blocks2);
-    int blockLen = normalizeVectors(blocks1, blocks2);
+    size_t blockLen = normalizeVectors(blocks1, blocks2);
 
-    for (int i = 0; i < blockLen; ++i) {
+    for (size_t i = 0; i < blockLen; ++i) {
         vector<string> tokens1;
         vector<string> tokens2;
         split(blocks1[i], '.', tokens1);
         split(blocks2[i], '.', tokens2);
-        int tokLen = normalizeVectors(tokens1, tokens2);
+        size_t tokLen = normalizeVectors(tokens1, tokens2);
 
-        for (int j = 0; j < tokLen; ++j) {
+        for (size_t j = 0; j < tokLen; ++j) {
             if (tokens1[j] == tokens2[j]) {
                 continue;
             }
@@ -67,8 +67,8 @@ COMP_RESULT compareVersions(const string& v1, const string& v2)
 
                 tokenizeMixed(tokens1[j], subtokens1);
                 tokenizeMixed(tokens2[j], subtokens2);
-                int subTokLen = normalizeVectors(subtokens1, subtokens2);
-                for (int k = 0; k < subTokLen; ++k) {
+                size_t subTokLen = normalizeVectors(subtokens1, subtokens2);
+                for (size_t k = 0; k < subTokLen; ++k) {
                     long sl1 = strtol(subtokens1[k].c_str(), &error1, 10);
                     long sl2 = strtol(subtokens2[k].c_str(), &error2, 10);
                     if (*error1 == 0 && *error2 == 0) {
@@ -123,9 +123,9 @@ COMP_RESULT compareVersions(const string& v1, const string& v2)
     return EQUAL;
 }
 
-int normalizeVectors(vector<string>& v1, vector<string>& v2)
+size_t normalizeVectors(vector<string>& v1, vector<string>& v2)
 {
-    int length = max(v1.size(), v2.size());
+    size_t length = max(v1.size(), v2.size());
 
     while (v1.size() < length) {
         v1.push_back("-1");
@@ -140,14 +140,14 @@ int normalizeVectors(vector<string>& v1, vector<string>& v2)
 void tokenizeMixed(const string& s, vector<string>& tokens)
 {
     vector<bool> digitMask;
-    for (int i = 0; i < s.length(); ++i) {
+    for (size_t i = 0; i < s.length(); ++i) {
         digitMask.push_back(isdigit(s[i]));
     }
 
     bool state = digitMask[0];
     string tok;
     tok = s[0];
-    for (int i = 1; i < digitMask.size(); ++i) {
+    for (size_t i = 1; i < digitMask.size(); ++i) {
         if (digitMask[i] != state) {
             tokens.push_back(tok);
             tok = s[i];
diff --git a/src/versioncomparator.h b/src/versioncomparator.h
index 767b148..bdda33c 100644
--- a/src/versioncomparator.h
+++ b/src/versioncomparator.h
@@ -19,7 +19,7 @@ enum COMP_RESULT { LESS, GREATER, EQUAL, UNDEFINED };
 
 COMP_RESULT compareVersions(const string& v1, const string& v2) ;
 void tokenizeIntoBlocks(const string& version, vector<string>& blocks);
-int normalizeVectors(vector<string>& v1, vector<string>& v2);
+size_t normalizeVectors(vector<string>& v1, vector<string>& v2);
 void tokenizeMixed(const string& s, vector<string>& tokens);
 
 }