[PATCH] Initialize m_hFile in FileMapping constructor.

Hi,

Find attached a patch that fixes compilation on gcc 4.6.2 (OpenSUSE
12.1 + Tumbleweed) with the following autogen.lastrun:
--enable-werror
--enable-kde4
--with-num-cpus=2
--with-max-jobs=2

See commit message for more details.

What I don't understand is why am I the only one hitting this. I think
GCC only does the analysis to warn about uninitialized variables when
compiled with optimization, but still: am I the only one with this GCC
version that compiled with optimization and --enable-werror?

From 78d778a79cfe2292d03ac30bee825147cc56ead9 Mon Sep 17 00:00:00 2001
From: Catalin Iacob <iacobcatalin@gmail.com>
Date: Wed, 14 Mar 2012 23:35:49 +0100
Subject: [PATCH] Initialize m_hFile in FileMapping constructor.

GCC gives the following warning which breaks compilation when using --enable-werror:
lockbyte.cxx: In function 'storeError 
store::FileLockBytes_createInstance(rtl::Reference<store::ILockBytes>&, rtl_uString*, 
storeAccessMode)':
lockbyte.css:512:37: error: 'prephitmp.221' may be used uninitialized in this function 
[-Werror=uninitialized]
lockbyte.cxx:906:1: note: 'prephitmp.221' was declared here

It's not clear from GCC's message, but what it warns about is
FileMapping::m_hFile. This is because of the following sequence:
* xMapping.release() makes xMapping.m_value be a default constructed
  FileMapping
* the xMapping local variable in store::FileLockBytes_createInstance
  gets destructed
* ~ResourceHolder() calls ResourceHolder::reset
* ResourceHolder::reset() calls FileMapping::UnmapFile::operator()
  passing m_value as rMapping
* FileMapping::UnmapFile::operator() uses rMapping.m_hFile but
  rMapping is a default constructed FileMapping and therefore has
  m_hFile uninitialized
---
 store/source/lockbyte.cxx |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/store/source/lockbyte.cxx b/store/source/lockbyte.cxx
index e28bffe..1a8bf81 100644
--- a/store/source/lockbyte.cxx
+++ b/store/source/lockbyte.cxx
@@ -478,7 +478,7 @@ struct FileMapping
     sal_uInt32  m_nSize;
     oslFileHandle m_hFile;
 
-    FileMapping() : m_pAddr(0), m_nSize(0) {}
+    FileMapping() : m_pAddr(0), m_nSize(0), m_hFile() {}
 
     bool operator != (FileMapping const & rhs) const
     {
-- 
1.7.9.2