fix #13977: false negative: unreadVariable with unrelated function call after rvalue declaration (regression) (#7702)

Author: ludviggunne

lib/fwdanalysis.cpp

@@ -76,7 +76,7 @@ static bool hasGccCompoundStatement(const Token *tok)
 
 static bool nonLocal(const Variable* var, bool deref)
 {
-    return !var || (!var->isLocal() && !var->isArgument()) || (deref && var->isArgument() && var->isPointer()) || var->isStatic() || var->isReference() || var->isExtern();
+    return !var || (!var->isLocal() && !var->isArgument()) || (deref && var->isArgument() && var->isPointer()) || var->isStatic() || var->isExtern();
 }
 
 static bool hasVolatileCastOrVar(const Token *expr)

lib/tokenlist.cpp

@@ -1762,10 +1762,10 @@ static Token * createAstAtToken(Token *tok)
         }
     }
 
-    if (Token::Match(tok, "%type% %name%|*|&|::") && !Token::Match(tok, "return|new|delete")) {
+    if (Token::Match(tok, "%type% %name%|*|&|&&|::") && !Token::Match(tok, "return|new|delete")) {
         int typecount = 0;
         Token *typetok = tok;
-        while (Token::Match(typetok, "%type%|::|*|&")) {
+        while (Token::Match(typetok, "%type%|::|*|&|&&")) {
             if (typetok->isName() && !Token::simpleMatch(typetok->previous(), "::"))
                 typecount++;
             typetok = typetok->next();

test/testtokenize.cpp

@@ -404,6 +404,7 @@ class TestTokenizer : public TestFixture {
         TEST_CASE(astnewscoped);
         TEST_CASE(astdecltypescope);
         TEST_CASE(astdesignatedinit);
+        TEST_CASE(astrvaluedecl);
 
         TEST_CASE(startOfExecutableScope);
 
@@ -7181,6 +7182,10 @@ class TestTokenizer : public TestFixture {
         ASSERT_EQUALS("(( f ({ (= (. x) 1)))", testAst("f({ .x = 1 });", AstStyle::Z3));
     }
 
+    void astrvaluedecl() {
+        ASSERT_EQUALS("varstdmove::var(=", testAst("std::string&& var = std::move(var);"));
+    }
+
 #define isStartOfExecutableScope(offset, code) isStartOfExecutableScope_(offset, code, __FILE__, __LINE__)
     template<size_t size>
     bool isStartOfExecutableScope_(int offset, const char (&code)[size], const char* file, int line) {

test/testunusedvar.cpp

@@ -188,6 +188,7 @@ class TestUnusedVar : public TestFixture {
         TEST_CASE(localvarconst2);
         TEST_CASE(localvarreturn); // ticket #9167
         TEST_CASE(localvarmaybeunused);
+        TEST_CASE(localvarrvalue); // ticket #13977
 
         TEST_CASE(localvarthrow); // ticket #3687
 
@@ -5200,10 +5201,9 @@ class TestUnusedVar : public TestFixture {
                               "    const auto&& c = g();\n"
                               "    auto&& d = c;\n"
                               "}\n");
-        TODO_ASSERT_EQUALS("[test.cpp:5:20]: (style) Variable 'b' is assigned a value that is never used.\n"
-                           "[test.cpp:7:14]: (style) Variable 'd' is assigned a value that is never used. [unreadVariable]\n",
-                           "[test.cpp:7:14]: (style) Variable 'd' is assigned a value that is never used. [unreadVariable]\n",
-                           errout_str());
+        ASSERT_EQUALS("[test.cpp:5:19]: (style) Variable 'b' is assigned a value that is never used. [unreadVariable]\n"
+                      "[test.cpp:7:14]: (style) Variable 'd' is assigned a value that is never used. [unreadVariable]\n",
+                      errout_str());
     }
 
     void localvaralias21() { // #11728
@@ -6473,6 +6473,15 @@ class TestUnusedVar : public TestFixture {
         ASSERT_EQUALS("", errout_str());
     }
 
+    void localvarrvalue() { // ticket #13977
+        functionVariableUsage("void f(void) {\n"
+                              "    std::string s;\n"
+                              "    std::string&& m = std::move(s);\n"
+                              "    cb();\n"
+                              "}\n");
+        ASSERT_EQUALS("[test.cpp:3:21]: (style) Variable 'm' is assigned a value that is never used. [unreadVariable]\n", errout_str());
+    }
+
     void localvarthrow() { // ticket #3687
         functionVariableUsage("void foo() {\n"
                               "    try {}"