some minor optimizations (#4449)

* cppcheck.cpp: reduced scope of a variable

* cppcheck.cpp: removed unnecessary severity checks

* cppcheck.cpp: avoid unnecessary copy

* templatesimplifier.cpp: perform early exit in loop in `expandTemplate()`

Author: firewave

lib/cppcheck.cpp

@@ -911,21 +911,21 @@ unsigned int CppCheck::checkFile(const std::string& filename, const std::string
                     ErrorMessage::FileLocation loc(e.token, &tokenizer.list);
                     locationList.push_back(loc);
                 } else {
-                    ErrorMessage::FileLocation loc(tokenizer.list.getSourceFilePath(), 0, 0);
                     ErrorMessage::FileLocation loc2(filename, 0, 0);
                     locationList.push_back(loc2);
-                    if (filename != tokenizer.list.getSourceFilePath())
+                    if (filename != tokenizer.list.getSourceFilePath()) {
+                        ErrorMessage::FileLocation loc(tokenizer.list.getSourceFilePath(), 0, 0);
                         locationList.push_back(loc);
+                    }
                 }
-                ErrorMessage errmsg(locationList,
+                ErrorMessage errmsg(std::move(locationList),
                                     tokenizer.list.getSourceFilePath(),
                                     Severity::error,
                                     e.errorMessage,
                                     e.id,
                                     Certainty::normal);
 
-                if (errmsg.severity == Severity::error || mSettings.severity.isEnabled(errmsg.severity))
-                    reportErr(errmsg);
+                reportErr(errmsg);
             }
         }
 

lib/templatesimplifier.cpp

@@ -2179,6 +2179,10 @@ void TemplateSimplifier::expandTemplate(
                         continue;
                 }
 
+                // don't add instantiations in template definitions
+                if (!templates.empty())
+                    continue;
+
                 std::string scope;
                 const Token *prev = tok3;
                 for (; Token::Match(prev->tokAt(-2), "%name% ::"); prev = prev->tokAt(-2)) {
@@ -2202,13 +2206,10 @@ void TemplateSimplifier::expandTemplate(
                     }
                 }
 
-                // don't add instantiations in template definitions
-                if (templates.empty()) {
-                    if (copy)
-                        newInstantiations.emplace_back(mTokenList.back(), scope);
-                    else if (!inTemplateDefinition)
-                        newInstantiations.emplace_back(tok3, scope);
-                }
+                if (copy)
+                    newInstantiations.emplace_back(mTokenList.back(), scope);
+                else if (!inTemplateDefinition)
+                    newInstantiations.emplace_back(tok3, scope);
             }
 
             // link() newly tokens manually