Fixed #9415 (C++11: `alignas` not handled -> wrong code -> false negatives)

lib/tokenize.cpp

@@ -4781,6 +4781,8 @@ bool Tokenizer::simplifyTokenList1(const char FileName[])
     // Remove extra "template" tokens that are not used by cppcheck
     removeExtraTemplateKeywords();
 
+    removeAlignas();
+
     // Bail out if code is garbage
     if (mTimerResults) {
         Timer t("Tokenizer::tokenize::findGarbageCode", mSettings->showtime, mTimerResults);
@@ -10905,6 +10907,19 @@ void Tokenizer::simplifyCPPAttribute()
     }
 }
 
+void Tokenizer::removeAlignas()
+{
+    if (!isCPP() || mSettings->standards.cpp < Standards::CPP11)
+        return;
+
+    for (Token *tok = list.front(); tok; tok = tok->next()) {
+        if (Token::Match(tok, "alignas|alignof (")) {
+            Token::eraseTokens(tok, tok->linkAt(1)->next());
+            tok->deleteThis();
+        }
+    }
+}
+
 static const std::unordered_set<std::string> keywords = {
     "inline"
     , "_inline"

lib/tokenize.h

@@ -692,6 +692,9 @@ private:
      */
     void simplifyCppcheckAttribute();
 
+    /** Remove alignas */
+    void removeAlignas();
+
     /**
      * Remove keywords "volatile", "inline", "register", and "restrict"
      */

test/testtokenize.cpp

@@ -414,6 +414,8 @@ private:
         TEST_CASE(checkHeader1);
 
         TEST_CASE(removeExtraTemplateKeywords);
+
+        TEST_CASE(removeAlignas);
     }
 
     std::string tokenizeAndStringify(const char code[], bool expand = true, Settings::PlatformType platform = Settings::Native, const char* filename = "test.cpp", bool cpp11 = true) {
@@ -6497,6 +6499,12 @@ private:
         const char expected2[] = "GridView :: Codim < 0 > :: Iterator it ; it = gv . begin < 0 > ( ) ;";
         ASSERT_EQUALS(expected2, tokenizeAndStringify(code2));
     }
+
+    void removeAlignas() {
+        const char code[] = "alignas(float) unsigned char c[sizeof(float)];";
+        const char expected[] = "unsigned char c [ sizeof ( float ) ] ;";
+        ASSERT_EQUALS(expected, tokenizeAndStringify(code));
+    }
 };
 
 REGISTER_TEST(TestTokenizer)