diff --git a/cli/cmdlineparser.cpp b/cli/cmdlineparser.cpp
index 7ed0f6a69..b08579e7b 100644
--- a/cli/cmdlineparser.cpp
+++ b/cli/cmdlineparser.cpp
@@ -401,7 +401,7 @@ bool CmdLineParser::ParseFromArgs(int argc, const char* const argv[])
             }
 
             // No "=", append a "=1"
-            if (define.find("=") == std::string::npos)
+            if (define.find('=') == std::string::npos)
                 define += "=1";
 
             if (!_settings->userDefines.empty())
diff --git a/lib/checktype.cpp b/lib/checktype.cpp
index 6dea55dc6..c669d4ff2 100644
--- a/lib/checktype.cpp
+++ b/lib/checktype.cpp
@@ -53,7 +53,7 @@ static bool astGetSizeSign(const Settings *settings, const Token *tok, unsigned
         return !tok->astOperand2() || astGetSizeSign(settings, tok->astOperand2(), size, sign);
     }
     if (tok->isNumber() && MathLib::isInt(tok->str())) {
-        if (tok->str().find("L") != std::string::npos)
+        if (tok->str().find('L') != std::string::npos)
             return false;
         MathLib::bigint value = MathLib::toLongNumber(tok->str());
         unsigned int sz;
diff --git a/lib/checkunusedvar.cpp b/lib/checkunusedvar.cpp
index ffd470ff4..a2583e3d1 100644
--- a/lib/checkunusedvar.cpp
+++ b/lib/checkunusedvar.cpp
@@ -1224,24 +1224,24 @@ void CheckUnusedVar::checkStructMemberUsage()
             structname.clear();
 
         if (!structname.empty() && Token::Match(tok, "[{;]")) {
-            // Declaring struct variable..
-            std::string varname;
-
             // declaring a POD variable?
             if (!tok->next()->isStandardType())
                 continue;
 
+            // Declaring struct variable..
+            const std::string* varname;
+
             if (Token::Match(tok->next(), "%type% %name% [;[]"))
-                varname = tok->strAt(2);
+                varname = &tok->strAt(2);
             else if (Token::Match(tok->next(), "%type% %type%|* %name% [;[]"))
-                varname = tok->strAt(3);
+                varname = &tok->strAt(3);
             else if (Token::Match(tok->next(), "%type% %type% * %name% [;[]"))
-                varname = tok->strAt(4);
+                varname = &tok->strAt(4);
             else
                 continue;
 
             // Check if the struct variable is used anywhere in the file
-            const std::string usagePattern(". " + varname);
+            const std::string usagePattern(". " + *varname);
             bool used = false;
             for (const Token *tok2 = _tokenizer->tokens(); tok2; tok2 = tok2->next()) {
                 if (Token::simpleMatch(tok2, usagePattern.c_str())) {
@@ -1251,7 +1251,7 @@ void CheckUnusedVar::checkStructMemberUsage()
             }
 
             if (! used) {
-                unusedStructMemberError(tok->next(), structname, varname);
+                unusedStructMemberError(tok->next(), structname, *varname);
             }
         }
     }
diff --git a/lib/errorlogger.cpp b/lib/errorlogger.cpp
index 3b59f83f4..488112748 100644
--- a/lib/errorlogger.cpp
+++ b/lib/errorlogger.cpp
@@ -88,7 +88,7 @@ void ErrorLogger::ErrorMessage::setmsg(const std::string &msg)
     // The summary and verbose message are separated by a newline
     // If there is no newline then both the summary and verbose messages
     // are the given message
-    const std::string::size_type pos = msg.find("\n");
+    const std::string::size_type pos = msg.find('\n');
     if (pos == std::string::npos) {
         _shortMessage = msg;
         _verboseMessage = msg;
diff --git a/lib/mathlib.cpp b/lib/mathlib.cpp
index f36707df5..9ef2b2af1 100644
--- a/lib/mathlib.cpp
+++ b/lib/mathlib.cpp
@@ -397,7 +397,7 @@ template<> std::string MathLib::toString(double value)
     result << value;
     if (result.str() == "-0")
         return "0.0";
-    if (result.str().find(".") == std::string::npos)
+    if (result.str().find('.') == std::string::npos)
         return result.str() + ".0";
     return result.str();
 }
diff --git a/lib/settings.cpp b/lib/settings.cpp
index a867b93af..89b0593a4 100644
--- a/lib/settings.cpp
+++ b/lib/settings.cpp
@@ -78,10 +78,10 @@ namespace {
 std::string Settings::addEnabled(const std::string &str)
 {
     // Enable parameters may be comma separated...
-    if (str.find(",") != std::string::npos) {
+    if (str.find(',') != std::string::npos) {
         std::string::size_type prevPos = 0;
         std::string::size_type pos = 0;
-        while ((pos = str.find(",", pos)) != std::string::npos) {
+        while ((pos = str.find(',', pos)) != std::string::npos) {
             if (pos == prevPos)
                 return std::string("cppcheck: --enable parameter is empty");
             const std::string errmsg(addEnabled(str.substr(prevPos, pos - prevPos)));
diff --git a/lib/suppressions.cpp b/lib/suppressions.cpp
index 03d7efc7f..1529ff881 100644
--- a/lib/suppressions.cpp
+++ b/lib/suppressions.cpp
@@ -66,11 +66,11 @@ std::string Suppressions::addSuppressionLine(const std::string &line)
             // is a line number..
 
             // Get position of last colon
-            const std::string::size_type pos = file.rfind(":");
+            const std::string::size_type pos = file.rfind(':');
 
             // if a colon is found and there is no dot after it..
             if (pos != std::string::npos &&
-                file.find(".", pos) == std::string::npos) {
+                file.find('.', pos) == std::string::npos) {
                 // Try to parse out the line number
                 try {
                     std::istringstream istr1(file.substr(pos+1));
diff --git a/lib/symboldatabase.cpp b/lib/symboldatabase.cpp
index 5ffde1d93..bdab26afb 100644
--- a/lib/symboldatabase.cpp
+++ b/lib/symboldatabase.cpp
@@ -3192,8 +3192,8 @@ const Function* Scope::findFunction(const Token *tok, bool requireConst) const
                 if (MathLib::isInt(arguments[j]->str())) {
                     if (arguments[j]->str().find("ll") != std::string::npos ||
                         arguments[j]->str().find("LL") != std::string::npos) {
-                        if (arguments[j]->str().find("u") != std::string::npos ||
-                            arguments[j]->str().find("U") != std::string::npos) {
+                        if (arguments[j]->str().find('u') != std::string::npos ||
+                            arguments[j]->str().find('U') != std::string::npos) {
                             if (funcarg->typeStartToken()->str() == "long" &&
                                 funcarg->typeStartToken()->isLong() &&
                                 funcarg->typeStartToken()->isUnsigned()) {
@@ -3206,10 +3206,10 @@ const Function* Scope::findFunction(const Token *tok, bool requireConst) const
                                 same++;
                             }
                         }
-                    } else if (arguments[j]->str().find("l") != std::string::npos ||
-                               arguments[j]->str().find("L") != std::string::npos) {
-                        if (arguments[j]->str().find("u") != std::string::npos ||
-                            arguments[j]->str().find("U") != std::string::npos) {
+                    } else if (arguments[j]->str().find('l') != std::string::npos ||
+                               arguments[j]->str().find('L') != std::string::npos) {
+                        if (arguments[j]->str().find('u') != std::string::npos ||
+                            arguments[j]->str().find('U') != std::string::npos) {
                             if (funcarg->typeStartToken()->str() == "long" &&
                                 !funcarg->typeStartToken()->isLong() &&
                                 funcarg->typeStartToken()->isUnsigned()) {
@@ -3222,8 +3222,8 @@ const Function* Scope::findFunction(const Token *tok, bool requireConst) const
                                 same++;
                             }
                         }
-                    } else if (arguments[j]->str().find("u") != std::string::npos ||
-                               arguments[j]->str().find("U") != std::string::npos) {
+                    } else if (arguments[j]->str().find('u') != std::string::npos ||
+                               arguments[j]->str().find('U') != std::string::npos) {
                         if (funcarg->typeStartToken()->str() == "int" &&
                             funcarg->typeStartToken()->isUnsigned()) {
                             same++;
@@ -3239,13 +3239,13 @@ const Function* Scope::findFunction(const Token *tok, bool requireConst) const
                         }
                     }
                 } else {
-                    if (arguments[j]->str().find("f") != std::string::npos ||
-                        arguments[j]->str().find("F") != std::string::npos) {
+                    if (arguments[j]->str().find('f') != std::string::npos ||
+                        arguments[j]->str().find('F') != std::string::npos) {
                         if (funcarg->typeStartToken()->str() == "float") {
                             same++;
                         }
-                    } else if (arguments[j]->str().find("l") != std::string::npos ||
-                               arguments[j]->str().find("L") != std::string::npos) {
+                    } else if (arguments[j]->str().find('l') != std::string::npos ||
+                               arguments[j]->str().find('L') != std::string::npos) {
                         if (funcarg->typeStartToken()->str() == "double" &&
                             funcarg->typeStartToken()->isLong())  {
                             same++;
@@ -3344,8 +3344,8 @@ const Function* SymbolDatabase::findFunction(const Token *tok) const
 
         if (currScope) {
             while (currScope && !Token::Match(tok1, "%type% :: %any% (")) {
-                currScope = currScope->findRecordInNestedList(tok1->strAt(2));
                 tok1 = tok1->tokAt(2);
+                currScope = currScope->findRecordInNestedList(tok1->str());
             }
 
             tok1 = tok1->tokAt(2);
diff --git a/lib/templatesimplifier.cpp b/lib/templatesimplifier.cpp
index b22643c74..a9cccb678 100644
--- a/lib/templatesimplifier.cpp
+++ b/lib/templatesimplifier.cpp
@@ -943,7 +943,7 @@ bool TemplateSimplifier::simplifyNumericCalculations(Token *tok)
     while (tok->tokAt(4) && tok->next()->isNumber() && tok->tokAt(3)->isNumber()) { // %any% %num% %any% %num% %any%
         const Token* op = tok->tokAt(2);
         const Token* after = tok->tokAt(4);
-        if (Token::Match(tok, "* %num% /") && (tok->strAt(3) != "0") && tok->next()->str() == MathLib::multiply(tok->strAt(3), MathLib::divide(tok->next()->str(), tok->strAt(3)))) {
+        if (Token::Match(tok, "* %num% /") && (op->strAt(1) != "0") && tok->next()->str() == MathLib::multiply(op->strAt(1), MathLib::divide(tok->next()->str(), op->strAt(1)))) {
             // Division where result is a whole number
         } else if (!((op->str() == "*" && (isLowerThanMulDiv(tok) || tok->str() == "*") && isLowerEqualThanMulDiv(after)) || // associative
                      (Token::Match(op, "[/%]") && isLowerThanMulDiv(tok) && isLowerEqualThanMulDiv(after)) || // NOT associative
diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index 276f16f01..b6286988a 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -1506,14 +1506,14 @@ void Tokenizer::simplifyTypedef()
                         }
                     } else if (typeOf) {
                         tok2 = copyTokens(tok2, argStart, argEnd);
-                    } else if (tok2->tokAt(2) && tok2->strAt(2) == "[") {
-                        while (tok2->tokAt(2) && tok2->strAt(2) == "[") {
+                    } else if (tok2->strAt(2) == "[") {
+                        do {
                             if (!tok2->linkAt(2)) {
                                 syntaxError(tok2); // #6807
                                 return;
                             }
                             tok2 = tok2->linkAt(2)->previous();
-                        }
+                        } while (tok2->strAt(2) == "[");
                     }
 
                     if (arrayStart && arrayEnd) {
@@ -2864,9 +2864,10 @@ void Tokenizer::setVarId()
     if (!isC()) {
         for (Token *tok2 = list.front(); tok2; tok2 = tok2->next()) {
             if (Token::Match(tok2, "%name% :: %name%")) {
-                if (tok2->strAt(3) == "(")
+                const std::string& str3 = tok2->strAt(3);
+                if (str3 == "(")
                     allMemberFunctions.push_back(tok2);
-                else if (tok2->strAt(3) != "::" && tok2->strAt(-1) != "::") // Support only one depth
+                else if (str3 != "::" && tok2->strAt(-1) != "::") // Support only one depth
                     allMemberVars.push_back(tok2);
             }
         }