Fixed #1477 (false positive: Uninitialized variable when pointer given to struct)

lib/tokenize.cpp

@@ -1242,6 +1242,9 @@ bool Tokenizer::tokenize(std::istream &code, const char FileName[], const std::s
 
     simplifyConst();
 
+    // struct initialization (must be used before simplifyVarDecl)
+    simplifyStructInit();
+
     // Split up variable declarations.
     simplifyVarDecl();
 
@@ -1264,6 +1267,7 @@ bool Tokenizer::tokenize(std::istream &code, const char FileName[], const std::s
     simplifyFunctionPointers();
 //updateClassList();
     setVarId();
+
     if (!validate())
         return false;
 
@@ -6535,6 +6539,59 @@ std::string Tokenizer::simplifyString(const std::string &source)
     return str;
 }
 
+
+void Tokenizer::simplifyStructInit()
+{
+    for (Token *tok = _tokens; tok; tok = tok->next())
+    {
+        if (Token::Match(tok, "[;{}] struct| %type% %var% = { . %type% ="))
+        {
+            // Goto "." and check if the initializations have an expected format
+            const Token *tok2 = tok;
+            while (tok2->str() != ".")
+                tok2 = tok2->next();
+            while (tok2 && tok2->str() == ".")
+            {
+                if (Token::Match(tok2, ". %type% = %num% [,}]"))
+                    tok2 = tok2->tokAt(4);
+                else if (Token::Match(tok2, ". %type% = %var% [,}]"))
+                    tok2 = tok2->tokAt(4);
+                else if (Token::Match(tok2, ". %type% = & %var% [,}]"))
+                    tok2 = tok2->tokAt(5);
+
+                if (Token::simpleMatch(tok2, ", ."))
+                    tok2 = tok2->next();
+            }
+            if (!Token::Match(tok2, "} ;"))
+                continue;
+
+            // Known expression format => Perform simplification
+            Token *vartok = tok->tokAt(3);
+            if (vartok->str() == "=")
+                vartok = vartok->previous();
+            vartok->next()->str(";");
+
+            Token *tok3 = vartok->tokAt(2);
+            tok3->link(0);
+            while (Token::Match(tok3, "[{,] . %type% ="))
+            {
+                tok3->str(vartok->str());
+                tok3->varId(vartok->varId());
+                tok3 = tok3->tokAt(5);
+                while (!Token::Match(tok3, "[,}]"))
+                    tok3 = tok3->next();
+                if (tok3->str() == "}")
+                {
+                    tok3->deleteThis();
+                    break;
+                }
+                tok3->previous()->insertToken(";");
+            }
+        }
+    }
+}
+
+
 void Tokenizer::simplifyComparisonOrder()
 {
     // Use "<" comparison instead of ">"

lib/tokenize.h

@@ -290,6 +290,9 @@ private:
      */
     bool simplifyFunctionReturn();
 
+    /** Struct initialization */
+    void simplifyStructInit();
+
     /**
      * Remove redundant paranthesis:
      * - "((x))" => "(x)"

test/testsimplifytokens.cpp

@@ -222,6 +222,9 @@ private:
 
         // while(fclose(f)); => r = fclose(f); while(r){r=fclose(f);}
         TEST_CASE(simplifyFuncInWhile);
+
+        // struct ABC abc = { .a = 3 };  =>  struct ABC abc; abc.a = 3;
+        TEST_CASE(initstruct);
     }
 
     std::string tok(const char code[], bool simplify = true)
@@ -4102,6 +4105,14 @@ private:
                       "}",
                       tok("while(fclose(f)); while(fclose(g));"));
     }
+
+    void initstruct()
+    {
+        ASSERT_EQUALS("; struct A a ; a . buf = 3 ;", tok("; struct A a = { .buf = 3 };"));
+        ASSERT_EQUALS("; struct A a ; a . buf = x ;", tok("; struct A a = { .buf = x };"));
+        ASSERT_EQUALS("; struct A a ; a . buf = & key ;", tok("; struct A a = { .buf = &key };"));
+        ASSERT_EQUALS("; struct ABC abc ; abc . a = 3 ; abc . b = x ; abc . c = & key ;", tok("; struct ABC abc = { .a = 3, .b = x, .c = &key };"));
+    }
 };
 
 REGISTER_TEST(TestSimplifyTokens)