Fixed false positive va_list_usedBeforeStarted (#7527)

lib/checkvaarg.cpp

@@ -122,7 +122,7 @@ void CheckVaarg::va_list_usage()
                 }
                 open = nopen;
                 tok = tok->linkAt(1);
-            } else if (Token::Match(tok, "throw|return"))
+            } else if (Token::Match(tok, "throw|return|break"))
                 exitOnEndOfStatement = true;
             else if (_tokenizer->isCPP() && tok->str() == "try") {
                 open = false;

test/testvaarg.cpp

@@ -200,6 +200,22 @@ private:
               "    va_end(v2);\n"
               "}");
         ASSERT_EQUALS("", errout.str());
+
+        // #7527
+        check("void foo(int flag1, int flag2, ...) {\n"
+              "    switch (flag1) {\n"
+              "    default:\n"
+              "        va_list vargs;\n"
+              "        va_start(vargs, flag2);\n"
+              "        if (flag2) {\n"
+              "            va_end(vargs);\n"
+              "            break;\n"
+              "        }\n"
+              "        int data = va_arg(vargs, int);\n"
+              "        va_end(vargs);\n"
+              "    }\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void va_start_subsequentCalls() {