diff --git a/libgrive/CMakeLists.txt b/libgrive/CMakeLists.txt
index f3aa775..90ef451 100644
--- a/libgrive/CMakeLists.txt
+++ b/libgrive/CMakeLists.txt
@@ -14,6 +14,8 @@ find_package(ZLIB)
 find_package(PkgConfig)
 pkg_check_modules(YAJL REQUIRED yajl)
 
+add_definitions(-Wall)
+
 # additional headers if build unit tests
 IF ( CPPUNIT_FOUND )
 	set( OPT_INCS		${CPPUNIT_INCLUDE_DIR} )
diff --git a/libgrive/src/base/Resource.cc b/libgrive/src/base/Resource.cc
index 7860516..9b75292 100644
--- a/libgrive/src/base/Resource.cc
+++ b/libgrive/src/base/Resource.cc
@@ -47,18 +47,18 @@ Resource::Resource( const fs::path& root_folder ) :
 	m_kind		( "folder" ),
 	m_id		( "folder:root" ),
 	m_href		( "root" ),
-	m_parent	( 0 ),
-	m_state		( sync ),
-	m_is_editable( true )
+	m_is_editable( true ),
+	m_parent	( NULL ),
+	m_state		( sync )
 {
 }
 
 Resource::Resource( const std::string& name, const std::string& kind ) :
 	m_name		( name ),
 	m_kind		( kind ),
-	m_parent	( 0 ),
-	m_state		( unknown ),
-	m_is_editable( true )
+	m_is_editable( true ),
+	m_parent	( NULL ),
+	m_state		( unknown )
 {
 }
 
diff --git a/libgrive/src/base/Resource.hh b/libgrive/src/base/Resource.hh
index cb712c6..bc342a7 100644
--- a/libgrive/src/base/Resource.hh
+++ b/libgrive/src/base/Resource.hh
@@ -152,6 +152,7 @@ private :
 	std::vector<Resource*>	m_child ;
 
 	State					m_state ;
+	Val*					m_json ;
 } ;
 
 } // end of namespace gr::v1
diff --git a/libgrive/src/base/State.cc b/libgrive/src/base/State.cc
index fb64a47..c3f7cc2 100644
--- a/libgrive/src/base/State.cc
+++ b/libgrive/src/base/State.cc
@@ -342,51 +342,49 @@ void State::ChangeStamp( long cstamp )
 
 bool State::Move( Syncer* syncer, fs::path old_p, fs::path new_p, fs::path grive_root )
 {
-	//Convert paths to canonical representations
-	//Also seems to remove trailing / at the end of directory paths
+	// Convert paths to canonical representations
+	// Also seems to remove trailing / at the end of directory paths
 	old_p = fs::canonical( old_p );
 	grive_root = fs::canonical( grive_root );
 	
-	//new_p is a little special because fs::canonical() requires that the path exists
-	if ( new_p.string()[ new_p.string().size() - 1 ] == '/') //If new_p ends with a /, remove it
+	// new_p is a little special because fs::canonical() requires that the path exists
+	if ( new_p.string()[ new_p.string().size() - 1 ] == '/') // If new_p ends with a /, remove it
 		new_p = new_p.parent_path();
 	new_p = fs::canonical( new_p.parent_path() ) / new_p.filename();
 	
-	//Fails if source file doesn't exist, or if destination file already
-	//exists and is not a directory, or if the source and destination are exactly the same
-	if ( (fs::exists(new_p) && !fs::is_directory(new_p) ) || !fs::exists(old_p) || fs::equivalent( old_p, new_p ) )
+	// Fails if source file doesn't exist, or if destination file already
+	// exists and is not a directory, or if the source and destination are exactly the same
+	if ( (fs::exists(new_p) && !fs::is_directory(new_p)) || !fs::exists(old_p) || fs::equivalent( old_p, new_p ) )
 		return false;
 	
-	//If new path is an existing directory, move the file into the directory
-	//instead of trying to rename it
-	if ( fs::is_directory(new_p) ){
+	// If new path is an existing directory, move the file into the directory
+	// instead of trying to rename it
+	if ( fs::is_directory( new_p ) )
 		new_p = new_p / old_p.filename();
-	}
 	
-	//Get the paths relative to grive root.
-	//Just finds the substring from the end of the grive_root to the end of the path
-	//+1s are to exclude slash at beginning of relative path
-	int start = grive_root.string().size() + 1;
-	int nLen = new_p.string().size() - (grive_root.string().size() + 1);
-	int oLen = old_p.string().size() - (grive_root.string().size() + 1);
-	if ( start + nLen != new_p.string().size() || start + oLen != old_p.string().size() )
+	// Get the paths relative to grive root.
+	// Just finds the substring from the end of the grive_root to the end of the path
+	// +1s are to exclude slash at beginning of relative path
+	std::string root( grive_root.string() + "/" );
+	if ( new_p.string().substr( 0, root.length() ).compare( root ) != 0 ||
+		old_p.string().substr( 0, root.length() ).compare( root ) != 0 )
 		return false;
-	fs::path new_p_rootrel( new_p.string().substr( start, nLen ) );
-	fs::path old_p_rootrel( old_p.string().substr( start, oLen ) );
+	fs::path new_p_rootrel( new_p.string().substr( root.length() ) );
+	fs::path old_p_rootrel( old_p.string().substr( root.length() ) );
 	
 	//Get resources
 	Resource* res = m_res.Root();
 	Resource* newParentRes = m_res.Root();
 	for ( fs::path::iterator it = old_p_rootrel.begin(); it != old_p_rootrel.end(); ++it )
 	{
-		if ( *it != "." && *it != ".." && res != 0 )
+		if ( *it != "." && *it != ".." && res )
 			res = res->FindChild(it->string());
 		if ( *it == ".." )
 			res = res->Parent();
 	}
 	for ( fs::path::iterator it = new_p_rootrel.begin(); it != new_p_rootrel.end(); ++it )
 	{
-		if ( *it != "." && *it != ".." && *it != new_p.filename() && newParentRes != 0 )
+		if ( *it != "." && *it != ".." && *it != new_p.filename() && newParentRes )
 			newParentRes = newParentRes->FindChild(it->string());
 		if ( *it == "..")
 			res = res->Parent();
diff --git a/libgrive/src/drive2/Syncer2.cc b/libgrive/src/drive2/Syncer2.cc
index 3455181..5151279 100644
--- a/libgrive/src/drive2/Syncer2.cc
+++ b/libgrive/src/drive2/Syncer2.cc
@@ -121,11 +121,10 @@ bool Syncer2::Move( Resource* res, Resource* newParentRes, std::string newFilena
 		http::Header hdr2 ;
 		hdr2.Add( "Content-Type: application/json" );
 		http::ValResponse vrsp ;
-		long http_code = 0;
 		//Don't change modified date because we're only moving
-		http_code = m_http->Put( feeds::files + "/" + res->ResourceID() + "?modifiedDateBehavior=noChange" + addRemoveParents, json_meta, &vrsp, hdr2 ) ;
+		long http_code = m_http->Put( feeds::files + "/" + res->ResourceID() + "?modifiedDateBehavior=noChange" + addRemoveParents, json_meta, &vrsp, hdr2 ) ;
 		valr = vrsp.Response();
-		assert( !( valr["id"].Str().empty() ) );
+		assert( http_code == 200 && !( valr["id"].Str().empty() ) );
 	}
 	return true;
 }
@@ -167,7 +166,7 @@ bool Syncer2::Upload( Resource *res )
 		else
 			http_code = m_http->Put( feeds::files + "/" + res->ResourceID(), json_meta, &vrsp, hdr2 ) ;
 		valr = vrsp.Response();
-		assert( !( valr["id"].Str().empty() ) );
+		assert( http_code == 200 && !( valr["id"].Str().empty() ) );
 	}
 	else
 	{
diff --git a/libgrive/src/protocol/OAuth2.cc b/libgrive/src/protocol/OAuth2.cc
index cd3dd6a..73ae088 100644
--- a/libgrive/src/protocol/OAuth2.cc
+++ b/libgrive/src/protocol/OAuth2.cc
@@ -37,8 +37,8 @@ OAuth2::OAuth2(
 	const std::string& refresh_code,
 	const std::string&	client_id,
 	const std::string&	client_secret ) :
-	m_agent( agent ),
 	m_refresh( refresh_code ),
+	m_agent( agent ),
 	m_client_id( client_id ),
 	m_client_secret( client_secret )
 {
diff --git a/libgrive/src/util/ConcatStream.cc b/libgrive/src/util/ConcatStream.cc
index effec72..d93df5e 100644
--- a/libgrive/src/util/ConcatStream.cc
+++ b/libgrive/src/util/ConcatStream.cc
@@ -23,7 +23,7 @@
 namespace gr {
 
 ConcatStream::ConcatStream() :
-	m_cur( 0 ), m_size( 0 ), m_pos( 0 )
+	m_size( 0 ), m_pos( 0 ), m_cur( 0 )
 {
 }
 
@@ -63,13 +63,13 @@ off_t ConcatStream::Seek( off_t offset, int whence )
 		offset += m_pos;
 	else if ( whence == 2 )
 		offset += Size();
-	if ( offset > Size() )
+	if ( (u64_t)offset > Size() )
 		offset = Size();
 	m_cur = 0;
 	m_pos = offset;
 	if ( m_streams.size() )
 	{
-		while ( offset > m_sizes[m_cur] )
+		while ( (u64_t)offset > m_sizes[m_cur] )
 			m_cur++;
 		m_streams[m_cur]->Seek( offset - ( m_cur > 0 ? m_sizes[m_cur-1] : 0 ), 0 );
 	}
@@ -90,7 +90,7 @@ void ConcatStream::Append( SeekStream *stream )
 {
 	if ( stream )
 	{
-		off_t size = stream->Size();
+		u64_t size = stream->Size();
 		if ( size > 0 )
 		{
 			// "fix" stream size at the moment of adding so further changes of underlying files
diff --git a/libgrive/src/util/ConcatStream.hh b/libgrive/src/util/ConcatStream.hh
index 0ab037e..0966f06 100644
--- a/libgrive/src/util/ConcatStream.hh
+++ b/libgrive/src/util/ConcatStream.hh
@@ -41,9 +41,9 @@ public :
 
 private :
 	std::vector<SeekStream*> m_streams ;
-	std::vector<off_t> m_sizes ;
-	off_t m_size, m_pos ;
-	int m_cur ;
+	std::vector<u64_t> m_sizes ;
+	u64_t m_size, m_pos ;
+	size_t m_cur ;
 } ;
 
 } // end of namespace
diff --git a/libgrive/src/util/StringStream.cc b/libgrive/src/util/StringStream.cc
index a128f74..447f892 100644
--- a/libgrive/src/util/StringStream.cc
+++ b/libgrive/src/util/StringStream.cc
@@ -51,7 +51,7 @@ off_t StringStream::Seek( off_t offset, int whence )
 		offset += m_pos;
 	else if ( whence == 2 )
 		offset += Size();
-	if ( offset > Size() )
+	if ( (u64_t)offset > Size() )
 		offset = Size();
 	m_pos = (size_t)offset;
 	return m_pos;