Unused value: Fix false positive (ast, {})

danmar · danmar · commit 37416010efa7 · 2018-12-14T18:56:09.000+01:00
diff --git a/lib/astutils.cpp b/lib/astutils.cpp
@@ -1084,17 +1084,15 @@ struct FwdAnalysis::Result FwdAnalysis::checkRecursive(const Token *expr, const
         if (Token::Match(tok, "return|throw")) {
             // TODO: Handle these better
             // Is expr variable used in expression?
-            bool read = false;
-            visitAstNodes(tok->astOperand1(),
-            [&](const Token *tok2) {
+            const Token *end = tok->findExpressionStartEndTokens().second->next();
+            for (const Token *tok2 = tok; tok2 != end; tok2 = tok2->next()) {
                 if (!local && Token::Match(tok2, "%name% ("))
-                    read = true;
+                    return Result(Result::Type::READ);
                 if (tok2->varId() && exprVarIds.find(tok2->varId()) != exprVarIds.end())
-                    read = true;
-                return read ? ChildrenToVisit::done : ChildrenToVisit::op1_and_op2;
-            });
+                    return Result(Result::Type::READ);
+            }
 
-            return Result(read ? Result::Type::READ : Result::Type::RETURN);
+            return Result(Result::Type::RETURN);
         }
 
         if (tok->str() == "}") {
diff --git a/lib/token.cpp b/lib/token.cpp
@@ -1215,6 +1215,8 @@ std::pair<const Token *, const Token *> Token::findExpressionStartEndTokens() co
 
     start = goToLeftParenthesis(start, end);
     end = goToRightParenthesis(start, end);
+    if (Token::simpleMatch(end, "{"))
+        end = end->link();
     return std::pair<const Token *, const Token *>(start,end);
 }
 
diff --git a/test/testtoken.cpp b/test/testtoken.cpp
@@ -939,6 +939,9 @@ class TestToken : public TestFixture {
         givenACodeSampleToTokenize var2("typedef unsigned long long u64; void f() { *((u64 *)x) = 0; }");
         const Token *const tok2 = Token::findsimplematch(var2.tokens(), "*");
         ASSERT_EQUALS("*((unsigned long long*)x)", tok2->expressionString());
+
+        givenACodeSampleToTokenize data3("return (t){1,2};");
+        ASSERT_EQUALS("return(t){1,2}", data3.tokens()->expressionString());
     }
 };
 
diff --git a/test/testunusedvar.cpp b/test/testunusedvar.cpp
@@ -107,6 +107,7 @@ class TestUnusedVar : public TestFixture {
         TEST_CASE(localvar51); // ticket #8128 - FN : tok = tok->next();
         TEST_CASE(localvar52);
         TEST_CASE(localvar53); // continue
+        TEST_CASE(localvar54); // ast, {}
         TEST_CASE(localvaralias1);
         TEST_CASE(localvaralias2); // ticket #1637
         TEST_CASE(localvaralias3); // ticket #1639
@@ -2109,6 +2110,14 @@ class TestUnusedVar : public TestFixture {
         // TODO ASSERT_EQUALS("[test.cpp:5]: (style) Variable 'x' is assigned a value that is never used.\n", errout.str());
     }
 
+    void localvar54() {
+        functionVariableUsage("Padding fun() {\n"
+                              "  Distance d = DISTANCE;\n"
+                              "  return (Padding){ d, d, d, d };\n"
+                              "}\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void localvaralias1() {
         functionVariableUsage("void foo()\n"
                               "{\n"

Original file line number	Diff line number	Diff line change
`@@ -1215,6 +1215,8 @@ std::pair<const Token , const Token > Token::findExpressionStartEndTokens() co`
`1215`	`1215`
`1216`	`1216`	`start = goToLeftParenthesis(start, end);`
`1217`	`1217`	`end = goToRightParenthesis(start, end);`
	`1218`	`+ if (Token::simpleMatch(end, "{"))`
	`1219`	`+ end = end->link();`
`1218`	`1220`	`return std::pair<const Token , const Token >(start,end);`
`1219`	`1221`	`}`
`1220`	`1222`
Original file line number	Diff line number	Diff line change
`@@ -939,6 +939,9 @@ class TestToken : public TestFixture {`
`939`	`939`	`givenACodeSampleToTokenize var2("typedef unsigned long long u64; void f() { ((u64 )x) = 0; }");`
`940`	`940`	`const Token const tok2 = Token::findsimplematch(var2.tokens(), "");`
`941`	`941`	`ASSERT_EQUALS("((unsigned long long)x)", tok2->expressionString());`
	`942`	`+`
	`943`	`+ givenACodeSampleToTokenize data3("return (t){1,2};");`
	`944`	`+ ASSERT_EQUALS("return(t){1,2}", data3.tokens()->expressionString());`
`942`	`945`	`}`
`943`	`946`	`};`
`944`	`947`