value flow: don't perform value flow analysis in sizeof/typeof expressions

lib/valueflow.cpp

@@ -227,6 +227,10 @@ static void valueFlowBeforeCondition(TokenList *tokenlist, ErrorLogger *errorLog
                     break;
             }
 
+            // skip sizeof..
+            if (tok2->str() == ")" && Token::Match(tok2->link()->previous(), "typeof|sizeof ("))
+                tok2 = tok2->link();
+
             if (tok2->str() == "}") {
                 if (Token::findmatch(tok2->link(), "%varid%", tok2, varid)) {
                     if (settings->debugwarnings)

test/testvalueflow.cpp

@@ -182,6 +182,13 @@ private:
                "}";
         ASSERT_EQUALS(true, testValueOfX(code, 2U, 123));
 
+        // skip sizeof
+        code = "void f(int *x) {\n"
+               "    sizeof(x[0]);\n"
+               "    if (x==63){}\n"
+               "}";
+        ASSERT_EQUALS(false, testValueOfX(code, 2U, 63));
+
         // bailout: if/else/etc
         bailout("void f(int x) {\n"
                 "    if (x != 123) { b = x; }\n"