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Partial fix for #14576: Missing attribute alignas (aligned_storage case) #8307

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Partial fix for #14576: Missing attribute alignas (aligned_storage case) #8307

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2e22edc
Add test
ludviggunne Mar 7, 2026
ec4cdc2
Fix #14576 (aligned_storage)
ludviggunne Mar 7, 2026
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51 changes: 51 additions & 0 deletions lib/tokenize.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -5983,6 +5983,9 @@ bool Tokenizer::simplifyTokenList1(const char FileName[])
// Link < with >
createLinks2();

// Handle std::aligned_storage<...>
simplifyAlignedStorage();

// Mark C++ casts
markCppCasts();

Expand Down Expand Up @@ -11133,6 +11136,54 @@ void Tokenizer::simplifyNamespaceAliases()
}
}

void Tokenizer::simplifyAlignedStorage()
{
if (!isCPP())
return;

const Standards::cppstd_t std = mSettings.standards.cpp;
if (std < Standards::CPP11 || std >= Standards::CPP23)
return;

for (Token *tok = list.front(); tok; tok = tok->next()) {
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@danmar danmar Mar 11, 2026

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if tok becomes null in the loop body then yes there will be null pointer dereference when tok->next() is executed here. I am not sure if tok can become null but we do have some code like tok && .. that suggest that tok can become null..

if (!Token::simpleMatch(tok, "aligned_storage <"))
continue;

tok = tok->next();
const Token *end = tok->link();
tok = tok->next();
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@danmar danmar Mar 11, 2026

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this is redundant as far as I see and in theory tok will become null if "<" is the last token and then there will be a crash.


if (!tok)
break;

if (!end)
continue;

for (; tok != end; tok = tok->next()) {
if (Token::simpleMatch(tok, ",")) {
tok = tok->next();
break;
}

if (Token::Match(tok, "(|<"))
tok = tok->link();
}

std::string str;
for (; tok != end; tok = tok->next()) {
str += " " + tok->str();
}

str = str.substr(1);

if (!Token::Match(tok, "> :: type %name%"))
continue;

tok = tok->tokAt(3);
tok->addAttributeAlignas(str);
}
}

void Tokenizer::setDirectives(std::list<Directive> directives)
{
mDirectives = std::move(directives);
Expand Down
5 changes: 5 additions & 0 deletions lib/tokenize.h
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Expand Up @@ -528,6 +528,11 @@ class CPPCHECKLIB Tokenizer {
*/
void simplifyNamespaceAliases();

/**
* Handle std::aligned_storage<...>
*/
void simplifyAlignedStorage();

/**
* Convert C++17 style nested namespace to older style
*/
Expand Down
16 changes: 16 additions & 0 deletions test/testtokenize.cpp
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Expand Up @@ -284,6 +284,8 @@ class TestTokenizer : public TestFixture {
TEST_CASE(cppMaybeUnusedAfter2);
TEST_CASE(cppMaybeUnusedStructuredBinding);

TEST_CASE(simplifyAlignedStorage);

TEST_CASE(splitTemplateRightAngleBrackets);

TEST_CASE(cpp03template1);
Expand Down Expand Up @@ -4332,6 +4334,20 @@ class TestTokenizer : public TestFixture {
ASSERT(var2 && var2->isAttributeMaybeUnused());
}

void simplifyAlignedStorage() {
const char code[] = "std::aligned_storage<sizeof(long), alignof(long)>::type buffer;";
const char expected[] = "std :: aligned_storage < sizeof ( long ) , alignof ( long ) > :: type buffer ;";

SimpleTokenizer tokenizer(settings2, *this);
ASSERT(tokenizer.tokenize(code));

ASSERT_EQUALS(expected, tokenizer.tokens()->stringifyList(nullptr, false));

const Token *buffer = Token::findsimplematch(tokenizer.tokens(), "buffer");
ASSERT(buffer);
ASSERT(buffer->hasAttributeAlignas());
ASSERT_EQUALS("alignof ( long )", buffer->getAttributeAlignas()[0]);
}

void splitTemplateRightAngleBrackets() {
{
Expand Down
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