From f43d732f3381b8aea3d3af9ccdd2fdebdf372eae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Sun, 7 Apr 2013 04:25:10 +0200
Subject: [PATCH] Fixed #4691 (False positive: Mismatching bitmasks in
 switch())

---
 lib/checkassignif.cpp | 6 ++++++
 test/testassignif.cpp | 9 +++++++++
 2 files changed, 15 insertions(+)

diff --git a/lib/checkassignif.cpp b/lib/checkassignif.cpp
index 1b42405db..d660aacde 100644
--- a/lib/checkassignif.cpp
+++ b/lib/checkassignif.cpp
@@ -78,6 +78,8 @@ bool CheckAssignIf::assignIfParseScope(const Token * const assignTok,
                                        const char bitop,
                                        const MathLib::bigint num)
 {
+    bool ret = false;
+
     for (const Token *tok2 = startTok; tok2; tok2 = tok2->next()) {
         if (Token::Match(tok2->tokAt(2), "%varid% %cop% %num% ;", varid) && tok2->strAt(3) == std::string(1U, bitop)) {
             const MathLib::bigint num2 = MathLib::toLongNumber(tok2->strAt(4));
@@ -96,6 +98,10 @@ bool CheckAssignIf::assignIfParseScope(const Token * const assignTok,
             return true;
         if (tok2->str() == "}")
             return false;
+        if (Token::Match(tok2, "break|continue|return"))
+            ret = true;
+        if (ret && tok2->str() == ";")
+            return false;
         if (!islocal && Token::Match(tok2, "%var% (") && !Token::simpleMatch(tok2->next()->link(), ") {"))
             return true;
         if (Token::Match(tok2, "if|while (")) {
diff --git a/test/testassignif.cpp b/test/testassignif.cpp
index 910817012..0e61f78d8 100644
--- a/test/testassignif.cpp
+++ b/test/testassignif.cpp
@@ -177,6 +177,15 @@ private:
               "    int c = b & 1;\n"
               "}");
         ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:3]: (style) Mismatching bitmasks. Result is always 0 (X = Y & 0xf0; Z = X & 0x1; => Z=0).\n", errout.str());
+
+        check("void f(int a) {\n"
+              "    int b = a;"
+              "    switch (x) {\n"
+              "    case 1: b &= 1; break;\n"
+              "    case 2: b &= 2; break;\n"
+              "    };\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void compare() {