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Fix #14074 FP constParameterReference reported for std::array object when non-const pointer to internal data is returned #7890

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Fix #14074 FP constParameterReference reported for std::array object when non-const pointer to internal data is returned #7890

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1dfd306
Update valueflow.cpp
chrchr-github Oct 15, 2025
9714db6
Update testother.cpp
chrchr-github Oct 15, 2025
63feade
Update valueflow.cpp
chrchr-github Oct 15, 2025
4ff7d31
Update checkstl.cpp
chrchr-github Oct 15, 2025
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2 changes: 1 addition & 1 deletion lib/checkstl.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1091,7 +1091,7 @@ static const ValueFlow::Value* getInnerLifetime(const Token* tok,
if (!tok)
return nullptr;
for (const ValueFlow::Value& val : tok->values()) {
if (!val.isLocalLifetimeValue())
if (!val.isLocalLifetimeValue() && !val.isArgumentLifetimeValue())
continue;
if (contains({ValueFlow::Value::LifetimeKind::Address,
ValueFlow::Value::LifetimeKind::SubObject,
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2 changes: 1 addition & 1 deletion lib/valueflow.cpp
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Expand Up @@ -1796,7 +1796,7 @@ static std::vector<ValueFlow::LifetimeToken> getLifetimeTokens(const Token* tok,
if (Token::Match(tok->tokAt(-2), ". %name% (") && tok->tokAt(-2)->originalName() != "->" && astIsContainer(tok->tokAt(-2)->astOperand1())) {
const Library::Container* library = getLibraryContainer(tok->tokAt(-2)->astOperand1());
const Library::Container::Yield y = library->getYield(tok->strAt(-1));
if (y == Library::Container::Yield::AT_INDEX || y == Library::Container::Yield::ITEM) {
if (contains({Library::Container::Yield::AT_INDEX, Library::Container::Yield::ITEM, Library::Container::Yield::BUFFER, Library::Container::Yield::BUFFER_NT}, y)) {
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This is not correct, The buffer returns a pointer not a reference so it should not be used here.

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The function is called getLifetimeTokens() though?

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Its get the lifetime of a reference. Thats why the it only follows the function that return references(see here). Its similar to followReferences, but different as it will get the parent lifetime of a reference as well.

Originally, it was called getLifetimeVariable(and there is still an overload for this), but was renamed to getLifetimeTokens so it can handle expressions and multiple lifetimes.

The lifetime of pointers are set in valueflow in the token. For pointer to containers data() method, we set the lifetime here:

cppcheck/lib/valueflow.cpp

Line 3237 in 5f301d3

master.errorPath.emplace_back(parent->tokAt(2), "Pointer to container is created here.");

errorPath.emplace_back(tok->previous(), "Accessing container.");
return ValueFlow::LifetimeToken::setAddressOf(
getLifetimeTokens(tok->tokAt(-2)->astOperand1(), escape, std::move(errorPath), pred, settings, depth - 1),
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3 changes: 3 additions & 0 deletions test/testother.cpp
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Expand Up @@ -3960,6 +3960,9 @@ class TestOther : public TestFixture {

check("void push(V& v) { v.push_back({ .x = 1 }); }"); // #14010
ASSERT_EQUALS("", errout_str());

check("size_t* f(std::array<uint8_t, 128>& a) { return reinterpret_cast<size_t*>(a.data()); }\n"); // #14074
ASSERT_EQUALS("", errout_str());
}

void constParameterCallback() {
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