From 4d070f04e581c590495e8814bcda2295c6e6c082 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <hyd_danmar@users.sourceforge.net>
Date: Sat, 6 Dec 2008 16:25:24 +0000
Subject: [PATCH] Added check that detects unreachable code below a 'return'
 statement

---
 CheckOther.cpp | 35 ++++++++++++++++++++++++++++++++++-
 CheckOther.h   |  5 ++++-
 cppcheck.cpp   |  3 +++
 3 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/CheckOther.cpp b/CheckOther.cpp
index b5d47465c..b36eb1265 100644
--- a/CheckOther.cpp
+++ b/CheckOther.cpp
@@ -783,5 +783,38 @@ void CheckOther::CheckIncompleteStatement()
             _errorLogger->reportErr(errmsg.str());
         }
     }
-}
+}
+//---------------------------------------------------------------------------
+
+
+
+
+
+
+//---------------------------------------------------------------------------
+// Unreachable code below a 'return'
+//---------------------------------------------------------------------------
+
+void CheckOther::unreachableCode()
+{
+    const TOKEN *tok = TOKEN::findmatch( _tokenizer->tokens(), "[;{}] return" );
+    while ( tok )
+    {
+        // Locate the end of the 'return' statement
+        while ( tok && ! TOKEN::Match(tok, ";") )
+            tok = tok->next;
+
+        // Next token should be either "case", "default" or "}"
+        if (tok && tok->next && !TOKEN::Match( tok, "; case|default|}"))
+        {
+            std::ostringstream errmsg;
+            errmsg << _tokenizer->fileLine(tok->next) << ": Unreachable code below a 'return'";
+            _errorLogger->reportErr(errmsg.str());
+        }
+
+        // Find the next 'return' statement
+        tok = TOKEN::findmatch( tok, "[;{}] return" );
+    }
+}
+
 
diff --git a/CheckOther.h b/CheckOther.h
index 7e47b02a3..a8b67b8d3 100644
--- a/CheckOther.h
+++ b/CheckOther.h
@@ -69,7 +69,10 @@ public:
     void CheckCharVariable();
 
     // Incomplete statement. A statement that only contains a constant or variable
-    void CheckIncompleteStatement();
+    void CheckIncompleteStatement();
+
+    /** Unreachable code below a 'return' */
+    void unreachableCode();
 private:
     void CheckVariableScope_LookupVar( const TOKEN *tok1, const char varname[] );
 
diff --git a/cppcheck.cpp b/cppcheck.cpp
index 99431c73a..7862fe79c 100644
--- a/cppcheck.cpp
+++ b/cppcheck.cpp
@@ -319,6 +319,9 @@ void CppCheck::checkFile(const std::string &code, const char FileName[])
         // Check for various types of incomplete statements that could for example
         // mean that an ';' has been added by accident
         checkOther.CheckIncompleteStatement();
+
+        // Unreachable code below a 'return' statement
+        checkOther.unreachableCode();
     }
 }
 //---------------------------------------------------------------------------