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D - Bug : GC can't allocate a large buffer

reply yaneurao sun-inet.or.jp writes:
In Win9x , GC can't allocate large buffers like this.

byte [] v = new byte[4096*256];

GC can't allocate this. Somebody said something is wrong with GC,
but I don't think so.

When allocPage is failed , fullcollect would be called.
GetThreadContext in fullcollect returns FALSE.
and make an assert failure.

: Thread t = threads[n] ;
: if( !GetThreadContext( t.hdl, &context ) ){
:  assert(0) ;  // here
: }

Obviously t.hdl is the duplicated handle made by calling
getCurrentThreadHandle() from Thread.this() in std.thread.

But getCurrentThreadHandle can't duplicate this.
After DuplicateHandle is called, GetLastError says 'invalid handle' in Win9x.
(Now I can't guess why it is..)

That's all why GC can't allocate and GC looks to have a failure.
It is a very serious problem , I think. Fix required.

yaneurao.
Jan 05 2004
parent reply yaneurao sun-inet.or.jp writes:
In article <btcaa0$a6f$1 digitaldaemon.com>, yaneurao sun-inet.or.jp says...
In Win9x , GC can't allocate large buffers like this.

I've got to the back of it. getCurrentThreadHandle in std.thread ,
 thread_hdl currentProcess = cast(thread_hdl)-1 ; // here has a problem

< thread_hdl currentProcess = GetCurrentProcess() ; I don't know what 'cast(thread_hdl)-1' means... yaneurao.
Jan 05 2004
parent reply "Walter" <walter digitalmars.com> writes:
<yaneurao sun-inet.or.jp> wrote in message
news:btdpq3$2i0a$1 digitaldaemon.com...
 In article <btcaa0$a6f$1 digitaldaemon.com>, yaneurao sun-inet.or.jp

In Win9x , GC can't allocate large buffers like this.

I've got to the back of it. getCurrentThreadHandle in std.thread ,
 thread_hdl currentProcess = cast(thread_hdl)-1 ; // here has a problem

< thread_hdl currentProcess = GetCurrentProcess() ; I don't know what 'cast(thread_hdl)-1' means...

Perhaps it would make more sense if written: cast(thread_hdl)(-1)
Jan 22 2004
parent yaneurao <yaneurao_member pathlink.com> writes:
In article <bup47g$2o3v$2 digitaldaemon.com>, Walter says...
In Win9x , GC can't allocate large buffers like this.
 thread_hdl currentProcess = cast(thread_hdl)-1 ; // here has a problem

I don't know what 'cast(thread_hdl)-1' means...

cast(thread_hdl)(-1)

I couldn't understand it for a moment , since MSDN in Japanese doesn't say anything about it. after , I found the following description MSDN in English. : A pseudo handle is a special constant, currently (HANDLE)-1, that is interpreted as the current process handle. For compatibility with future operating systems, it is best to call GetCurrentProcess instead of hard-coding this constant value. it is just what I want to say! (HANDLE)-1 should not be used. in Win9x at least Japanese Edition , it is fact that calling DuplicateHandle with currentProcessHandle being -1 will fail. and that's why GC in D can't allocate a large buffer in Win9x. yaneurao.
Jan 22 2004