diff --git a/cplusplus/VError.cpp b/cplusplus/VError.cpp
index 67e67348..a3d82188 100644
--- a/cplusplus/VError.cpp
+++ b/cplusplus/VError.cpp
@@ -32,8 +32,6 @@
 #endif /*HAVE_CONFIG_H*/
 #include <vips/intl.h>
 
-#include <iostream>
-
 #include <vips/vips8>
 
 VIPS_NAMESPACE_START
diff --git a/cplusplus/VImage.cpp b/cplusplus/VImage.cpp
index 3c1acd98..205b46cb 100644
--- a/cplusplus/VImage.cpp
+++ b/cplusplus/VImage.cpp
@@ -563,7 +563,7 @@ VImage::new_from_file( const char *name, VOption *options )
 }
 
 VImage 
-VImage::new_from_buffer( void *buf, size_t len, const char *option_string, 
+VImage::new_from_buffer( const void *buf, size_t len, const char *option_string, 
 	VOption *options )
 {
 	const char *operation_name;
@@ -588,6 +588,13 @@ VImage::new_from_buffer( void *buf, size_t len, const char *option_string,
 	return( out );
 }
 
+VImage 
+VImage::new_from_buffer( const std::string &buf, const char *option_string, 
+	VOption *options )
+{
+	return( new_from_buffer( buf.c_str(), buf.size(), option_string, options ) );
+}
+
 VImage 
 VImage::new_matrix( int width, int height ) 
 {
diff --git a/cplusplus/include/vips/VError8.h b/cplusplus/include/vips/VError8.h
index 627222c1..29f3e9fb 100644
--- a/cplusplus/include/vips/VError8.h
+++ b/cplusplus/include/vips/VError8.h
@@ -31,8 +31,8 @@
 #ifndef VIPS_VERROR_H
 #define VIPS_VERROR_H
 
-#include <string>
-#include <iosfwd>
+#include <cstring>
+#include <ostream>
 #include <exception>
 
 #include <vips/vips.h>
@@ -43,7 +43,7 @@ class VIPS_CPLUSPLUS_API VError : public std::exception {
 	std::string _what;
 
 public:
-	VError( std::string what ) : _what( what ) {}
+	VError( const std::string &what ) : _what( what ) {}
 	VError() : _what( vips_error_buffer() ) {}
 	virtual ~VError() throw() {}
 
diff --git a/cplusplus/include/vips/VImage8.h b/cplusplus/include/vips/VImage8.h
index 05ae1a2e..abd0b78a 100644
--- a/cplusplus/include/vips/VImage8.h
+++ b/cplusplus/include/vips/VImage8.h
@@ -34,7 +34,7 @@
 #include <complex>
 #include <vector>
 
-#include <string.h>
+#include <cstring>
 
 #include <vips/vips.h>
 
@@ -327,6 +327,12 @@ public:
 		return( vips_image_get_yoffset( get_image() ) ); 
 	}
 
+	bool
+	has_alpha() const
+	{
+		return( vips_image_hasalpha( get_image() ) );
+	}
+
 	const char *
 	filename() const
 	{
@@ -416,6 +422,12 @@ public:
 		return( value ); 
 	}
 
+	bool
+	remove( const char *name ) const
+	{
+		return( vips_image_remove( get_image(), name ) );
+	}
+
 	static VOption *
 	option()
 	{
@@ -458,7 +470,10 @@ public:
 		return( VImage( image ) ); 
 	}
 
-	static VImage new_from_buffer( void *buf, size_t len,
+	static VImage new_from_buffer( const void *buf, size_t len,
+		const char *option_string, VOption *options = 0 );
+
+	static VImage new_from_buffer( const std::string &buf,
 		const char *option_string, VOption *options = 0 );
 
 	static VImage new_matrix( int width, int height );
@@ -495,6 +510,17 @@ public:
 		return( new_from_image( to_vectorv( 1, pixel ) ) ); 
 	}
 
+	VImage 
+	copy_memory() const
+	{
+		VipsImage *image;
+
+		if( !(image = vips_image_copy_memory( this->get_image() )) )
+			throw( VError() );
+
+		return( VImage( image ) );
+	}
+
 	VImage write( VImage out ) const;
 
 	void write_to_file( const char *name, VOption *options = 0 ) const;
diff --git a/cplusplus/include/vips/VInterpolate8.h b/cplusplus/include/vips/VInterpolate8.h
index 606a696a..8ef6f99e 100644
--- a/cplusplus/include/vips/VInterpolate8.h
+++ b/cplusplus/include/vips/VInterpolate8.h
@@ -34,7 +34,7 @@
 #include <complex>
 #include <vector>
 
-#include <string.h>
+#include <cstring>
 
 #include <vips/vips.h>
 
diff --git a/libvips/conversion/cast.c b/libvips/conversion/cast.c
index abdc8327..26fa7be4 100644
--- a/libvips/conversion/cast.c
+++ b/libvips/conversion/cast.c
@@ -194,11 +194,8 @@ G_DEFINE_TYPE( VipsCast, vips_cast, VIPS_TYPE_CONVERSION );
 	ITYPE * restrict p = (ITYPE *) in; \
 	OTYPE * restrict q = (OTYPE *) out; \
 	\
-	for( x = 0; x < sz; x++ ) { \
-		TEMP v = VIPS_FLOOR( p[x] ); \
-		\
-		q[x] = CAST( v ); \
-	} \
+	for( x = 0; x < sz; x++ ) \
+		q[x] = CAST( p[x] ); \
 }
 
 /* Cast complex types to an int type. Just take the real part.
@@ -208,10 +205,8 @@ G_DEFINE_TYPE( VipsCast, vips_cast, VIPS_TYPE_CONVERSION );
 	OTYPE * restrict q = (OTYPE *) out; \
 	\
 	for( x = 0; x < sz; x++ ) { \
-		TEMP v = VIPS_FLOOR( p[0] ); \
-		\
+		q[x] = CAST( p[0] ); \
 		p += 2; \
-		q[x] = CAST( v ); \
 	} \
 }