Kai Tietz wrote:
> There are a lot of issues about casting HANDLE values into jint types,
> which is for x86 valid, but for x64 can lead potential to pointer
> truncations. Those part need some review by libjava maintainers. My
> patch simply casts those kind of pointers via __UINTPTR_TYPE__ into
> integer scalar before casting it into jint. I put comments at those
> places, where some rework is necessary.
Argh. You're replacing a bunch of warnings that draw attention to a real
problem by a bunch of silent fixmes in the code. That's a bit scary to me.
> Index: gcc/libjava/gnu/java/net/natPlainSocketImplWin32.cc
> ===================================================================
> --- gcc.orig/libjava/gnu/java/net/natPlainSocketImplWin32.cc 2009-07-19
> 12:06:54.200476000 +0200
> +++ gcc/libjava/gnu/java/net/natPlainSocketImplWin32.cc 2009-07-19
> 12:13:45.727476500 +0200
> @@ -58,7 +58,8 @@
>
> // We use native_fd in place of fd here. From leaving fd null we avoid
> // the double close problem in FileDescriptor.finalize.
> - native_fd = (jint) hSocket;
> + // Fixme, it isn't correct to cast a HANDLE to integer scalar here for x64
> + native_fd = (jint) (__UINTPTR_TYPE__) hSocket;
> }
Question is, can we change the sizes of the members of class objects, such
as gnu::java::net::PlainSocketImpl::native_fd, or do these objects and their
layout form part of an ABI, and/or do they ever get serialised? The Java guys
will be able to tell us.
cheers,
DaveK
