From 085e97fd366126fe0d475fc8c55b079edb461738 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <hyd_danmar@users.sourceforge.net>
Date: Wed, 31 Dec 2008 09:02:45 +0000
Subject: [PATCH] Memory leak : Added check "Using resource after it has been
 released"

---
 checkmemoryleak.cpp | 20 +++++++++++++++++---
 testmemleak.cpp     | 17 +++++++++++++++++
 2 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/checkmemoryleak.cpp b/checkmemoryleak.cpp
index 363f2ba4d..56fb6086e 100644
--- a/checkmemoryleak.cpp
+++ b/checkmemoryleak.cpp
@@ -1088,11 +1088,26 @@ void CheckMemoryLeakClass::CheckMemoryLeak_CheckScope( const TOKEN *Tok1, const
     AllocType alloctype = No;
     AllocType dealloctype = No;
 
+    const TOKEN *result;
+
     TOKEN *tok = getcode( Tok1, callstack, varname, alloctype, dealloctype );
-    // tok->printOut( "getcode result" );
+    //tok->printOut( "getcode result" );
+
+    // Simplify the code and check if freed memory is used..
+    for ( TOKEN *tok2 = tok; tok2; tok2 = tok2->next() )
+    {
+        while ( TOKEN::Match(tok2, "[;{}] ;") )
+            erase(tok2, tok2->tokAt(2));
+    }
+    if ( (result = TOKEN::findmatch(tok, "dealloc [;{}] use ;")) != NULL )
+    {
+        std::ostringstream errmsg;
+        errmsg << _tokenizer->fileLine(result->tokAt(2)) << ": Using \"" << varname << "\" after it has been deallocated / released";
+        _errorLogger->reportErr( errmsg.str() );
+    }
 
     simplifycode( tok );
-    // tok->printOut( "simplifycode result" );
+    //tok->printOut( "simplifycode result" );
 
     // If the variable is not allocated at all => no memory leak
     if (TOKEN::findmatch(tok, "alloc") == 0)
@@ -1108,7 +1123,6 @@ void CheckMemoryLeakClass::CheckMemoryLeak_CheckScope( const TOKEN *Tok1, const
         return;
     }
 
-	const TOKEN *result;
     if ( (result = TOKEN::findmatch(tok, "loop alloc ;")) != NULL )
     {
         MemoryLeak(result, varname, alloctype);
diff --git a/testmemleak.cpp b/testmemleak.cpp
index b1c00c2ff..3370b5ea0 100644
--- a/testmemleak.cpp
+++ b/testmemleak.cpp
@@ -151,6 +151,8 @@ private:
 
 
         // TODO TEST_CASE( structmember1 );
+
+        TEST_CASE( dealloc_use_1 );     // Deallocate and then use memory
     }
 
 
@@ -1361,6 +1363,21 @@ private:
         ASSERT_EQUALS( std::string("[test.cpp:5]: Memory leak: abc.a\n"), errout.str() );
     }
 
+
+
+
+    void dealloc_use_1()
+    {
+        check( "void f()\n"
+               "{\n"
+               "    char *s = new char[100];\n"
+               "    delete [] s;\n"
+               "    p = s;\n"
+               "}\n" );
+        ASSERT_EQUALS( std::string("[test.cpp:5]: Using \"s\" after it has been deallocated / released\n"), errout.str() );
+    }
+
+
 };
 
 REGISTER_TEST( TestMemleak )