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

Author: ludviggunne

lib/tokenize.cpp

@@ -6011,6 +6011,9 @@ bool Tokenizer::simplifyTokenList1(const char FileName[])
     // Link < with >
     createLinks2();
 
+    // Handle std::aligned_storage<...>
+    simplifyAlignedStorage();
+
     // Mark C++ casts
     markCppCasts();
 
@@ -10361,6 +10364,8 @@ void Tokenizer::simplifyNamespaceStd()
                  mSettings.library.podtype("std::" + tok->str()) ||
                  isStdContainerOrIterator(tok, mSettings))
             insert = true;
+        else if (Token::simpleMatch(tok, "aligned_storage"))
+            insert = true;
 
         if (insert) {
             tok->previous()->insertToken("std");
@@ -11176,6 +11181,57 @@ 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()) {
+        if (!Token::simpleMatch(tok, "std :: aligned_storage <"))
+            continue;
+
+        tok = tok->tokAt(3);
+        const Token *end = tok->link();
+        tok = tok->next();
+
+        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();
+        }
+
+        if (str.empty())
+            continue;
+
+        if (!Token::Match(tok, "> :: type %name%"))
+            continue;
+
+        str = str.substr(1);
+
+        tok = tok->tokAt(3);
+        tok->addAttributeAlignas(str);
+    }
+}
+
 void Tokenizer::setDirectives(std::list<Directive> directives)
 {
     mDirectives = std::move(directives);

lib/tokenize.h

@@ -528,6 +528,11 @@ class CPPCHECKLIB Tokenizer {
      */
     void simplifyNamespaceAliases();
 
+    /**
+     * Handle std::aligned_storage<...>
+     */
+    void simplifyAlignedStorage();
+
     /**
      * Convert C++17 style nested namespace to older style
      */

test/testtokenize.cpp

@@ -292,6 +292,7 @@ class TestTokenizer : public TestFixture {
 
         TEST_CASE(attributeAlignasBefore);
         TEST_CASE(attributeAlignasAfter);
+        TEST_CASE(simplifyAlignedStorage);
 
         TEST_CASE(splitTemplateRightAngleBrackets);
 
@@ -4380,6 +4381,21 @@ class TestTokenizer : public TestFixture {
         ASSERT_EQUALS(var->getAttributeAlignas()[0], "long");
     }
 
+    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() {
         {
             const char code[] = "; z = x < 0 ? x >> y : x >> y;";