SymbolDatabase; Add variables when structured binding is used

lib/symboldatabase.cpp

@@ -4139,6 +4139,16 @@ const Token *Scope::checkVariable(const Token *tok, AccessControl varaccess, con
     // the start of the type tokens does not include the above modifiers
     const Token *typestart = tok;
 
+    // C++17 structured bindings
+    if (settings->standards.cpp >= Standards::CPP17 && Token::Match(tok, "auto &|&&| [")) {
+        const Token *typeend = Token::findsimplematch(typestart, "[")->previous();
+        for (tok = typeend->tokAt(2); Token::Match(tok, "%name%|,"); tok = tok->next()) {
+            if (tok->varId())
+                addVariable(tok, typestart, typeend, varaccess, nullptr, this, settings);
+        }
+        return typeend->linkAt(1);
+    }
+
     if (tok->isKeyword() && Token::Match(tok, "class|struct|union|enum")) {
         tok = tok->next();
     }

test/testsymboldatabase.cpp

@@ -346,6 +346,7 @@ private:
         TEST_CASE(symboldatabase91);
         TEST_CASE(symboldatabase92); // daca crash
         TEST_CASE(symboldatabase93); // alignas attribute
+        TEST_CASE(symboldatabase94); // structured bindings
 
         TEST_CASE(createSymbolDatabaseFindAllScopes1);
 
@@ -4712,6 +4713,13 @@ private:
         ASSERT(scope);
     }
 
+    void symboldatabase94() { // structured bindings
+        GET_SYMBOL_DB("int foo() { auto [x,y] = xy(); return x+y; }");
+        ASSERT(db != nullptr);
+        ASSERT(db->getVariableFromVarId(1) != nullptr);
+        ASSERT(db->getVariableFromVarId(2) != nullptr);
+    }
+
     void createSymbolDatabaseFindAllScopes1() {
         GET_SYMBOL_DB("void f() { union {int x; char *p;} a={0}; }");
         ASSERT(db->scopeList.size() == 3);