diff --git a/lib/checkbufferoverrun.cpp b/lib/checkbufferoverrun.cpp
index 520ed16a4..d896cd8ad 100644
--- a/lib/checkbufferoverrun.cpp
+++ b/lib/checkbufferoverrun.cpp
@@ -587,14 +587,14 @@ void CheckBufferOverrun::checkFunctionCall(const Token &tok, unsigned int par, c
                     if (Token::Match(ftok->previous(), "[=+-*/;{}] %var% [ %num% ]"))
                     {
                         long index = MathLib::toLongNumber(ftok->strAt(2));
-                        if (index >= arrayInfo.num[0])
+                        if (index >= 0 && static_cast<unsigned long>(index) >= arrayInfo.num[0])
                         {
                             std::list<const Token *> callstack;
                             callstack.push_back(&tok);
                             callstack.push_back(ftok);
 
                             std::vector<unsigned int> indexes;
-                            indexes.push_back(index);
+                            indexes.push_back(static_cast<unsigned long>(index));
 
                             arrayIndexOutOfBounds(callstack, arrayInfo, indexes);
                         }
@@ -989,16 +989,16 @@ void CheckBufferOverrun::checkScope(const Token *tok, const ArrayInfo &arrayInfo
         {
             if (tok->str() == "strncat")
             {
-                const unsigned int n = MathLib::toLongNumber(tok->strAt(6));
-                if (n >= total_size)
+                const long n = MathLib::toLongNumber(tok->strAt(6));
+                if (static_cast<unsigned long>(n) >= total_size)
                     strncatUsage(tok);
             }
 
             // Dangerous usage of strncpy + strncat..
             if (Token::Match(tok->tokAt(8), "; strncat ( %varid% , %any% , %num% )", arrayInfo.varid))
             {
-                const unsigned int n = MathLib::toLongNumber(tok->strAt(6)) + MathLib::toLongNumber(tok->strAt(15));
-                if (n > total_size)
+                const long n = MathLib::toLongNumber(tok->strAt(6)) + MathLib::toLongNumber(tok->strAt(15));
+                if (static_cast<unsigned long>(n) > total_size)
                     strncatUsage(tok->tokAt(9));
             }
         }
@@ -1041,8 +1041,8 @@ void CheckBufferOverrun::checkScope(const Token *tok, const ArrayInfo &arrayInfo
         // snprintf..
         if (Token::Match(tok, "snprintf ( %varid% , %num% ,", arrayInfo.varid))
         {
-            const unsigned int n = MathLib::toLongNumber(tok->strAt(4));
-            if (n > total_size)
+            const long n = MathLib::toLongNumber(tok->strAt(4));
+            if (static_cast<unsigned long>(n) > total_size)
                 outOfBounds(tok->tokAt(4), "snprintf size");
         }
     }
@@ -1759,10 +1759,13 @@ CheckBufferOverrun::ArrayInfo::ArrayInfo(unsigned int id, const std::string &nam
 
 CheckBufferOverrun::ArrayInfo CheckBufferOverrun::ArrayInfo::limit(long value) const
 {
+    unsigned long uvalue = (unsigned long)std::max(0L, value);
     unsigned int n = 1;
     for (unsigned int i = 0; i < num.size(); ++i)
         n *= num[i];
-    return ArrayInfo(varid, varname, element_size, value > (int)n ? 0 : n - value);
+    if (uvalue > n)
+        n = uvalue;
+    return ArrayInfo(varid, varname, element_size, n - uvalue);
 }
 
 bool CheckBufferOverrun::ArrayInfo::declare(const Token *tok, const Tokenizer &tokenizer)
@@ -1808,7 +1811,7 @@ bool CheckBufferOverrun::ArrayInfo::declare(const Token *tok, const Tokenizer &t
 
     while (Token::Match(atok, "%num% ] ;|=|["))
     {
-        _num.push_back(MathLib::toLongNumber(atok->str()));
+        _num.push_back((unsigned long)MathLib::toLongNumber(atok->str()));
         atok = atok->next();
         if (Token::simpleMatch(atok, "] ["))
             atok = atok->tokAt(2);
@@ -1881,7 +1884,7 @@ private:
         {
             ExecutionPathBufferOverrun *c = dynamic_cast<ExecutionPathBufferOverrun *>(*it);
             if (c && c->varId == varid)
-                c->value = MathLib::toLongNumber(value);
+                c->value = (unsigned long)MathLib::toLongNumber(value);
         }
     }
 
diff --git a/lib/checkmemoryleak.cpp b/lib/checkmemoryleak.cpp
index df866d463..658072e47 100644
--- a/lib/checkmemoryleak.cpp
+++ b/lib/checkmemoryleak.cpp
@@ -922,7 +922,7 @@ Token *CheckMemoryLeakInFunction::getcode(const Token *tok, std::list<const Toke
 
                 if (sz > 1 &&
                     Token::Match(tok->tokAt(2), "malloc ( %num% )") &&
-                    (MathLib::toLongNumber(tok->strAt(4)) % sz) != 0)
+                    (MathLib::toLongNumber(tok->strAt(4)) % long(sz)) != 0)
                 {
                     mismatchSizeError(tok->tokAt(4), tok->strAt(4));
                 }
diff --git a/lib/checkother.cpp b/lib/checkother.cpp
index b13ebda6c..11d1b254b 100644
--- a/lib/checkother.cpp
+++ b/lib/checkother.cpp
@@ -3380,8 +3380,8 @@ private:
                     if (Token::Match(tok.tokAt(6), "%num% )"))
                     {
                         const unsigned int len = Token::getStrLength(tok.tokAt(4));
-                        const unsigned int sz = MathLib::toLongNumber(tok.strAt(6));
-                        if (len>=sz)
+                        const long sz = MathLib::toLongNumber(tok.strAt(6));
+                        if (sz >= 0 && len >= static_cast<unsigned long>(sz))
                         {
                             init_strncpy(checks, tok.tokAt(2));
                             return tok.next()->link();
@@ -4050,7 +4050,7 @@ void CheckOther::nullPointerError(const Token *tok, const std::string &varname)
 
 void CheckOther::nullPointerError(const Token *tok, const std::string &varname, const unsigned int line)
 {
-    reportError(tok, Severity::error, "nullPointer", "Possible null pointer dereference: " + varname + " - otherwise it is redundant to check if " + varname + " is null at line " + MathLib::toString<long>(line));
+    reportError(tok, Severity::error, "nullPointer", "Possible null pointer dereference: " + varname + " - otherwise it is redundant to check if " + varname + " is null at line " + MathLib::toString<unsigned int>(line));
 }
 
 void CheckOther::uninitstringError(const Token *tok, const std::string &varname)
diff --git a/lib/cppcheck.cpp b/lib/cppcheck.cpp
index 0b400438f..334af55d0 100644
--- a/lib/cppcheck.cpp
+++ b/lib/cppcheck.cpp
@@ -64,7 +64,7 @@ public:
 struct TimerResultsData
 {
     std::clock_t _clocks;
-    unsigned int _numberOfResults;
+    long _numberOfResults;
 
     TimerResultsData()
         : _clocks(0)
diff --git a/lib/mathlib.cpp b/lib/mathlib.cpp
index f056e63ba..57c9ad05c 100644
--- a/lib/mathlib.cpp
+++ b/lib/mathlib.cpp
@@ -65,20 +65,6 @@ double MathLib::toDoubleNumber(const std::string &str)
     return ret;
 }
 
-template <typename T>
-std::string MathLib::toString(T d)
-{
-    std::ostringstream result;
-    result << d;
-    std::string strResult(result.str());
-    if (strResult == "-0"
-        || strResult == "+0"
-        || strResult == "-0."
-        || strResult == "+0.")
-        return std::string("0");
-    return result.str();
-}
-
 bool MathLib::isFloat(const std::string &s)
 {
     // every number that contains a . is a float
diff --git a/lib/mathlib.h b/lib/mathlib.h
index 017fc46d0..1ff4f6ccd 100644
--- a/lib/mathlib.h
+++ b/lib/mathlib.h
@@ -21,6 +21,7 @@
 #define mathlibH
 
 #include <string>
+#include <sstream>
 
 /// @addtogroup Core
 /// @{
@@ -36,7 +37,18 @@ public:
     static double toDoubleNumber(const std::string & str);
 
     template<typename T>
-    static std::string toString(T d);
+    static std::string toString(T d)
+    {
+        std::ostringstream result;
+        result << d;
+        std::string strResult(result.str());
+        if (strResult == "-0"
+            || strResult == "+0"
+            || strResult == "-0."
+            || strResult == "+0.")
+            return std::string("0");
+        return result.str();
+    }
 
     static bool isInt(const std::string & str);
     static bool isFloat(const std::string &str);
diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index 9bd00fca4..38c65cbbc 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -1849,13 +1849,13 @@ void Tokenizer::arraySize()
             }
 
             if (Token::Match(tok2, "%any% } ;"))
-                tok->next()->insertToken(MathLib::toString<long>(sz));
+                tok->next()->insertToken(MathLib::toString<unsigned int>(sz));
         }
 
         else if (Token::Match(tok, "%var% [ ] = %str% ;"))
         {
             unsigned int sz = tok->strAt(4).length() - 1;
-            tok->next()->insertToken(MathLib::toString<long>(sz));
+            tok->next()->insertToken(MathLib::toString<unsigned int>(sz));
         }
     }
 }
@@ -3142,17 +3142,17 @@ void Tokenizer::simplifySizeof()
                     continue;
                 }
 
-                sizeOfVar[varId] = MathLib::toString<long>(size);
+                sizeOfVar[varId] = MathLib::toString<unsigned int>(size);
             }
 
             else if (Token::Match(tok->tokAt(-1), "%type% %var% [ %num% ] [;=]") ||
                      Token::Match(tok->tokAt(-2), "%type% * %var% [ %num% ] [;=]"))
             {
-                unsigned int size = sizeOfType(tok->tokAt(-1));
+                const unsigned int size = sizeOfType(tok->tokAt(-1));
                 if (size == 0)
                     continue;
 
-                sizeOfVar[varId] = MathLib::toString<long>(size * MathLib::toLongNumber(tok->strAt(2)));
+                sizeOfVar[varId] = MathLib::toString<unsigned long>(size * static_cast<unsigned long>(MathLib::toLongNumber(tok->strAt(2))));
             }
 
             else if (Token::Match(tok->tokAt(-1), "%type% %var% [ %num% ] [,)]") ||
@@ -3165,11 +3165,11 @@ void Tokenizer::simplifySizeof()
 
             else if (Token::Match(tok->tokAt(-1), "%type% %var% [ ] = %str% ;"))
             {
-                unsigned int size = sizeOfType(tok->tokAt(4));
+                const unsigned int size = sizeOfType(tok->tokAt(4));
                 if (size == 0)
                     continue;
 
-                sizeOfVar[varId] = MathLib::toString<long>(size);
+                sizeOfVar[varId] = MathLib::toString<unsigned int>(size);
             }
         }
     }
@@ -3330,7 +3330,7 @@ void Tokenizer::simplifySizeof()
             unsigned int size = sizeOfType(tok->tokAt(2));
             if (size > 0)
             {
-                tok->str(MathLib::toString<long>(size));
+                tok->str(MathLib::toString<unsigned int>(size));
                 Token::eraseTokens(tok, tok->tokAt(4));
             }
         }
@@ -3361,7 +3361,7 @@ void Tokenizer::simplifySizeof()
 
             if (sz > 0)
             {
-                tok->str(MathLib::toString<long>(sz));
+                tok->str(MathLib::toString<unsigned int>(sz));
                 Token::eraseTokens(tok, tok->next()->link()->next());
             }
         }
@@ -7653,7 +7653,7 @@ void Tokenizer::simplifyStructDecl()
             {
                 std::string name;
 
-                name = "Anonymous" + MathLib::toString<long>(count++);
+                name = "Anonymous" + MathLib::toString<unsigned int>(count++);
 
                 tok1->insertToken(name.c_str());