From 121c0ee58f9c2bcbc44060c69f78937aca94909f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <hyd_danmar@users.sourceforge.net>
Date: Sat, 17 Jan 2009 11:12:15 +0000
Subject: [PATCH] unused variable: reading the value of variable in a for
 loop.. "for(;a;)" see ticket #18

---
 src/checkother.cpp     |  3 +++
 test/testunusedvar.cpp | 10 ++++++++++
 2 files changed, 13 insertions(+)

diff --git a/src/checkother.cpp b/src/checkother.cpp
index 66ddc2ca7..98c84d204 100644
--- a/src/checkother.cpp
+++ b/src/checkother.cpp
@@ -927,6 +927,9 @@ void CheckOther::functionVariableUsage()
 
             if (Token::Match(tok, "[(,] %var% [,)]"))
                 varUsage[ tok->strAt(1)] |= USAGE_WRITE;
+
+            if (Token::Match(tok, "; %var% ;"))
+                varUsage[ tok->strAt(1)] |= USAGE_READ;
         }
 
         // Check usage of all variables in the current scope..
diff --git a/test/testunusedvar.cpp b/test/testunusedvar.cpp
index 87946d389..1b531ba91 100644
--- a/test/testunusedvar.cpp
+++ b/test/testunusedvar.cpp
@@ -75,6 +75,7 @@ private:
         TEST_CASE(localvarIf);          // Usage in if
         TEST_CASE(localvarIfElse);      // return tmp1 ? tmp2 : tmp3;
         TEST_CASE(localvarOpAssign);    // a |= b;
+        TEST_CASE(localvarFor);         // for ( ; var; )
     }
 
     void structmember1()
@@ -335,6 +336,15 @@ private:
         ASSERT_EQUALS(std::string("[test.cpp:2]: Variable 'a' is assigned a value that is never used\n"), errout.str());
     }
 
+    void localvarFor()
+    {
+        functionVariableUsage("void foo()\n"
+                              "{\n"
+                              "    int a = 1;\n"
+                              "    for (;a;);\n"
+                              "}\n");
+        ASSERT_EQUALS(std::string(""), errout.str());
+    }
 
 };