Fixed two bugs in AST compilation (#5830):

- Correctly parse operators .* and ->*
- Support empty branch in ternary expression (a?:c)

lib/token.cpp

@@ -1094,19 +1094,27 @@ std::string Token::stringifyList(bool varid) const
 
 void Token::astOperand1(Token *tok)
 {
+    if (_astOperand1)
+        _astOperand1->_astParent = nullptr;
     // goto parent operator
-    while (tok->_astParent)
-        tok = tok->_astParent;
-    tok->_astParent = this;
+    if (tok) {
+        while (tok->_astParent)
+            tok = tok->_astParent;
+        tok->_astParent = this;
+    }
     _astOperand1 = tok;
 }
 
 void Token::astOperand2(Token *tok)
 {
+    if (_astOperand2)
+        _astOperand2->_astParent = nullptr;
     // goto parent operator
-    while (tok->_astParent)
-        tok = tok->_astParent;
-    tok->_astParent = this;
+    if (tok) {
+        while (tok->_astParent)
+            tok = tok->_astParent;
+        tok->_astParent = this;
+    }
     _astOperand2 = tok;
 }
 

lib/tokenlist.cpp

@@ -473,7 +473,7 @@ static void compileScope(Token *&tok, std::stack<Token*> &op, unsigned int depth
 static bool isPrefixUnary(const Token* tok)
 {
     if (!tok->previous()
-        || (Token::Match(tok->previous(), "(|[|{|%op%|;|}|?|:|,|return|throw")
+        || (Token::Match(tok->previous(), "(|[|{|%op%|;|}|?|:|,|.|return|throw")
             && (tok->previous()->type() != Token::eIncDecOp || tok->type() == Token::eIncDecOp)))
         return true;
 
@@ -486,7 +486,7 @@ static void compilePrecedence2(Token *&tok, std::stack<Token*> &op, unsigned int
     while (tok) {
         if (tok->type() == Token::eIncDecOp && !isPrefixUnary(tok)) {
             compileUnaryOp(tok, compileScope, op, depth);
-        } else if (tok->str() == ".") {
+        } else if (tok->str() == "." && tok->strAt(1) != "*") {
             compileBinOp(tok, compileScope, op, depth);
         } else if (tok->str() == "[") {
             Token* tok2 = tok;
@@ -530,9 +530,19 @@ static void compilePrecedence3(Token *&tok, std::stack<Token*> &op, unsigned int
     }
 }
 
-static void compileMulDiv(Token *&tok, std::stack<Token*> &op, unsigned int depth)
+static void compilePointerToElem(Token *&tok, std::stack<Token*> &op, unsigned int depth)
 {
     compilePrecedence3(tok, op, depth);
+    while (tok) {
+        if (Token::simpleMatch(tok, ". *")) {
+            compileBinOp(tok, compilePrecedence3, op, depth);
+        } else break;
+    }
+}
+
+static void compileMulDiv(Token *&tok, std::stack<Token*> &op, unsigned int depth)
+{
+    compilePointerToElem(tok, op, depth);
     while (tok) {
         if (Token::Match(tok, "[*/%]")) {
             if (Token::Match(tok, "* [*,)]")) {
@@ -540,11 +550,10 @@ static void compileMulDiv(Token *&tok, std::stack<Token*> &op, unsigned int dept
                 while (tok2->next() && tok2->str() == "*")
                     tok2 = tok2->next();
                 if (Token::Match(tok2, "[,)]")) {
-                    //tok = tok2->next();
                     break;
                 }
             }
-            compileBinOp(tok, compilePrecedence3, op, depth);
+            compileBinOp(tok, compilePointerToElem, op, depth);
         } else break;
     }
 }
@@ -646,6 +655,9 @@ static void compileAssignTernary(Token *&tok, std::stack<Token*> &op, unsigned i
         // TODO: http://en.cppreference.com/w/cpp/language/operator_precedence says:
         //       "The expression in the middle of the conditional operator (between ? and :) is parsed as if parenthesized: its precedence relative to ?: is ignored."
         if (tok->isAssignmentOp() || Token::Match(tok, "[?:]")) {
+            if (tok->str() == "?" && tok->strAt(1) == ":") {
+                op.push(0);
+            }
             compileBinOp(tok, compileAssignTernary, op, depth);
         } else break;
     }

test/testtokenize.cpp

@@ -10384,7 +10384,7 @@ private:
 
         // Basic AST validation
         for (const Token *tok = tokenList.front(); tok; tok = tok->next()) {
-            if (tok->astOperand2() && !tok->astOperand1() && tok->str() != ";")
+            if (tok->astOperand2() && !tok->astOperand1() && tok->str() != ";" && tok->str() != ":")
                 return "Op2 but no Op1 for token: " + tok->str();
         }
 
@@ -10433,6 +10433,8 @@ private:
         ASSERT_EQUALS("ab|=",  testAst("a|=b;"));
         ASSERT_EQUALS("ab^=",  testAst("a^=b;"));
 
+        ASSERT_EQUALS("ab*c*.(+return", testAst("return a + ((*b).*c)();"));
+
         // assignments are executed from right to left
         ASSERT_EQUALS("abc==", testAst("a=b=c;"));
 
@@ -10465,6 +10467,9 @@ private:
         ASSERT_EQUALS("ifx( i0= whilei(", testAst("if (x) { ({ int i = 0; while(i); }) };"));
         ASSERT_EQUALS("ifx( BUG_ON{!( i0= whilei(", testAst("if (x) { BUG_ON(!({int i=0; while(i);})); }"));
         ASSERT_EQUALS("v0= while{( v0= while{( v0=", testAst("({ v = 0; }); while (({ v = 0; }) != 0); while (({ v = 0; }) != 0);"));
+
+
+        ASSERT_EQUALS("abc.1:?1+bd.1:?+=", testAst("a =(b.c ? : 1) + 1 + (b.d ? : 1);"));
     }
 
     void astpar() const { // parentheses