Fix #12052 FP: containerOutOfBounds (#5534)

Author: chrchr-github

lib/checkstl.cpp

@@ -1930,8 +1930,8 @@ void CheckStl::string_c_str()
 
     // Find all functions that take std::string as argument
     struct StrArg {
-        nonneg int n; // cppcheck-suppress unusedStructMember // FP used through iterator/pair
-        std::string argtype; // cppcheck-suppress unusedStructMember
+        nonneg int n;
+        std::string argtype;
     };
     std::multimap<const Function*, StrArg> c_strFuncParam;
     if (printPerformance) {

lib/valueflow.cpp

@@ -8526,10 +8526,10 @@ static std::vector<ValueFlow::Value> getContainerSizeFromConstructorArgs(const s
 static bool valueFlowIsSameContainerType(const ValueType& contType, const Token* tok, const Settings* settings)
 {
     if (!tok || !tok->valueType() || !tok->valueType()->containerTypeToken)
-        return false;
+        return true;
 
     const ValueType tokType = ValueType::parseDecl(tok->valueType()->containerTypeToken, *settings);
-    return contType.isTypeEqual(&tokType);
+    return contType.isTypeEqual(&tokType) || tokType.type == ValueType::Type::UNKNOWN_TYPE;
 }
 
 static std::vector<ValueFlow::Value> getInitListSize(const Token* tok,

test/fixture.h

@@ -118,7 +118,7 @@ class TestFixture : public ErrorLogger {
     static T& getCheck()
     {
         for (Check *check : Check::instances()) {
-            //cppcheck-suppress [constVariablePointer, useStlAlgorithm] - TODO: fix constVariable FP
+            //cppcheck-suppress useStlAlgorithm
             if (T* c = dynamic_cast<T*>(check))
                 return *c;
         }

test/testvalueflow.cpp

@@ -6670,6 +6670,27 @@ class TestValueFlow : public TestFixture {
                "}\n";
         ASSERT(!isKnownContainerSizeValue(tokenValues(code, "v ["), 0).empty());
         ASSERT(!isPossibleContainerSizeValue(tokenValues(code, "v ["), 0).empty());
+
+        code = "template<typename T>\n" // #12052
+               "std::vector<T> g(T);\n"
+               "int f() {\n"
+               "    const std::vector<int> v{ g(3) };\n"
+               "    auto x = v.size();\n"
+               "    return x;\n"
+               "}\n";
+        ASSERT_EQUALS(false, testValueOfXKnown(code, 6U, 1));
+
+        code = "template<typename T>\n"
+               "std::vector<T> g(const std::stack<T>& s);\n"
+               "int f() {\n"
+               "    std::stack<int> s{};\n"
+               "    s.push(42);\n"
+               "    s.push(43);\n"
+               "    const std::vector<int> r{ g(s) };\n"
+               "    auto x = r.size();\n"
+               "    return x;\n"
+               "}\n";
+        ASSERT_EQUALS(false, testValueOfXKnown(code, 9U, 1));
     }
 
     void valueFlowContainerElement()