Fixed cppcheck-opensource#6863 (AST: wrong handling of assignment between ? and :)

danmar · danmar · commit 8ffa917fa2e2 · 2015-07-24T13:02:00.000+02:00
diff --git a/lib/tokenlist.cpp b/lib/tokenlist.cpp
@@ -427,7 +427,8 @@ struct AST_state {
     unsigned int depth;
     unsigned int inArrayAssignment;
     bool cpp;
-    explicit AST_state(bool cpp_) : depth(0), inArrayAssignment(0), cpp(cpp_) {}
+    unsigned int assign;
+    explicit AST_state(bool cpp_) : depth(0), inArrayAssignment(0), cpp(cpp_), assign(0U) {}
 };
 
 static bool iscast(const Token *tok)
@@ -847,10 +848,22 @@ static void compileAssignTernary(Token *&tok, AST_state& state)
     while (tok) {
         // 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) == ":") {
+        if (tok->isAssignmentOp()) {
+            state.assign++;
+            compileBinOp(tok, state, compileAssignTernary);
+            if (state.assign > 0U)
+                state.assign--;
+        } else if (tok->str() == "?") {
+            if (tok->strAt(1) == ":") {
                 state.op.push(0);
             }
+            const unsigned int assign = state.assign;
+            state.assign = 0U;
+            compileBinOp(tok, state, compileAssignTernary);
+            state.assign = assign;
+        } else if (tok->str() == ":") {
+            if (state.assign > 0U)
+                break;
             compileBinOp(tok, state, compileAssignTernary);
         } else break;
     }
diff --git a/test/testtokenize.cpp b/test/testtokenize.cpp
@@ -8413,6 +8413,9 @@ class TestTokenizer : public TestFixture {
         // assignments are executed from right to left
         ASSERT_EQUALS("abc==", testAst("a=b=c;"));
 
+        // assignment in ternary operator
+        ASSERT_EQUALS("ab0=c1=:?", testAst("a?b=0:c=1;"));
+
         ASSERT_EQUALS("a\"\"=", testAst("a=\"\""));
         ASSERT_EQUALS("a\'\'=", testAst("a=\'\'"));
         ASSERT_EQUALS("a1[\"\"=", testAst("char a[1]=\"\";"));
