Fix #14693 False positive: null pointer, std::string && val = {} (#8499)

Author: chrchr-github

lib/tokenlist.cpp

@@ -446,7 +446,7 @@ static Token* skipDecl(Token* tok, std::vector<Token*>* inner = nullptr)
     if (!Token::Match(tok->previous(), "( %name%"))
         return tok;
     Token *vartok = tok;
-    while (Token::Match(vartok, "%name%|*|&|::|<")) {
+    while (Token::Match(vartok, "%name%|*|&|&&|::|<")) {
         if (vartok->str() == "<") {
             if (vartok->link())
                 vartok = vartok->link();

test/testsymboldatabase.cpp

@@ -587,6 +587,7 @@ class TestSymbolDatabase : public TestFixture {
         TEST_CASE(valueType3);
         TEST_CASE(valueTypeThis);
         TEST_CASE(valueTypeChar);
+        TEST_CASE(valueTypeRValueReference);
 
         TEST_CASE(variadic1); // #7453
         TEST_CASE(variadic2); // #7649
@@ -10175,6 +10176,10 @@ class TestSymbolDatabase : public TestFixture {
         ASSERT_EQUALS("char", typeOf("char buf[10]; buf[0] = 'x';", "[ 0 ]", true, &s));
     }
 
+    void valueTypeRValueReference() {
+        TODO_ASSERT_EQUALS("", "bool", typeOf("void f(std::string&& s = {})", "&&"));
+    }
+
     void variadic1() { // #7453
         {
             GET_SYMBOL_DB("CBase* create(const char *c1, ...);\n"

test/testvalueflow.cpp

@@ -5277,6 +5277,12 @@ class TestValueFlow : public TestFixture {
                "    continuous_src_time(std::complex<double> f, double st = 0.0, double et = infinity) {}\n"
                "};";
         (void)testValueOfX(code, 2U, 2); // Don't crash (#6494)
+
+        code = "struct S {\n" // #14693
+               "    int i;\n"
+               "    explicit S(std::string&& s = {}) : i(0) {}\n"
+               "};";
+        ASSERT_EQUALS(false, testKnownValueOfTok(code, "{ } )", 0));
     }
 
     bool isNotKnownValues(const char code[], const char str[]) {