From 3b8e9f5a2a3a88cc9cc94c357b68dc9fcb2d3fd0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Tue, 3 Sep 2013 17:02:46 +0200
Subject: [PATCH] Fixed #4899 (False positive on unused variable)

---
 lib/checkunusedvar.cpp |  2 ++
 test/testunusedvar.cpp | 10 ++++++++++
 2 files changed, 12 insertions(+)

diff --git a/lib/checkunusedvar.cpp b/lib/checkunusedvar.cpp
index 9834de84d..8c5e760ac 100644
--- a/lib/checkunusedvar.cpp
+++ b/lib/checkunusedvar.cpp
@@ -462,6 +462,8 @@ static const Token* doAssignment(Variables &variables, const Token *tok, bool de
                         addressOf = true;
                         tok = tok->next();
                     }
+                } else if (Token::Match(tok, "%cop% %var%")) {
+                    variables.read(tok->next()->varId(), tok);
                 }
             }
 
diff --git a/test/testunusedvar.cpp b/test/testunusedvar.cpp
index 0409945b7..05da72ae0 100644
--- a/test/testunusedvar.cpp
+++ b/test/testunusedvar.cpp
@@ -92,6 +92,7 @@ private:
         TEST_CASE(localvar43); // ticket #3742
         TEST_CASE(localvar44); // ticket #3602
         TEST_CASE(localvar45); // ticket #4020
+        TEST_CASE(localvar46); // ticket #4899
         TEST_CASE(localvaralias1);
         TEST_CASE(localvaralias2); // ticket #1637
         TEST_CASE(localvaralias3); // ticket #1639
@@ -1821,6 +1822,15 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void localvar46() { // #4899 - FP
+        functionVariableUsage("int func() {\n"
+                              "    int a = 123;\n"
+                              "    int b = (short)-a;;\n"
+                              "    return b;\n"
+                              "}");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void localvaralias1() {
         functionVariableUsage("void foo()\n"
                               "{\n"