Re: Segfault while building on 64-bit Cygwin

2020-02-16 Thread John Cowan
Excellent, and thank you all!  I've been WIndowsless for a few weeks, but
that should change again soon.

On Sun, Feb 16, 2020 at 6:23 PM Mike Gran  wrote:

> On Fri, Feb 14, 2020 at 09:46:04AM -0800, Charles Stanhope wrote:
> > Andy, I don't know if you'd want to continue this here or on
> > lightening's gitlab page, but I looked into this a little bit a few
> > minutes here and there this past weeek. The x86 "fast-call" calling
> > convention used on Windows x64[0] and shared by Cygwin[1] requires
> > that the caller reserve 32 bytes of memory on the stack for the callee
> > to spill the register parameters (even if the callee takes fewer than
> > four parameters). I think lightening is currently missing that for the
> > x64 case for Cygwin.
> >
> > To test the idea, I made a small modification (patch attached) that is
> > *not* intended as a solution as it doesn't work for the general case,
> > but it does allow the tests to pass on Cygwin 64.
>
> I can confirm that Charles's patch, plus another one line patch
> to define CPU_SETSIZE, is enough to get Guile 3.0.x to build and run
> on my box.  All tests pass except strptime in French, and the absence
> of crypt.  This is a 64-bit build.
>
> -Mike Gran
>


Fixing `flush-output-port` for R6RS transcoded ports

2020-02-16 Thread Andreas Rottmann
Hi!

As I reported in #39610 [0], `flush-output-port`, aka `force-output` is
no longer working for R6RS transcoded ports. It was still working in
Guile 2.0; the regression was introduced in Guile 2.2, via commit
"8399e7af5 ("Generic port facility provides buffering uniformly").

I'd be interested in fixing this, but I'm unclear how to tackle it. From
a glance at the current code, it seems to me that there is no mechanism
in place that can be used to achieve that, as the `flush` method for
port types is no more, and I see no way to pass the `flush` operation on
transcoded port to the port it is wrapping. My gut approach would be to
re-introduce the `flush` operation, but I'm not sure that would be
sensible and/or fit into the re-architected ports.

If someone, perhaps @wingo (being the author of the re-factoring), could
sketch an implementation strategy (or just affirm that re-introducing
`flush` is sensible), I would be grateful, and would be one step further
in resurrecting my R6RS Scheme code after almost a decade of abandon.

[0] https://debbugs.gnu.org/cgi/bugreport.cgi?bug=39610

Kind Regards, Rotty




Re: Segfault while building on 64-bit Cygwin

2020-02-16 Thread Charles Stanhope
On 2/16/20, Mike Gran  wrote:
> On Fri, Feb 14, 2020 at 09:46:04AM -0800, Charles Stanhope wrote:
>> Andy, I don't know if you'd want to continue this here or on
>> lightening's gitlab page, but I looked into this a little bit a few
>> minutes here and there this past weeek. The x86 "fast-call" calling
>> convention used on Windows x64[0] and shared by Cygwin[1] requires
>> that the caller reserve 32 bytes of memory on the stack for the callee
>> to spill the register parameters (even if the callee takes fewer than
>> four parameters). I think lightening is currently missing that for the
>> x64 case for Cygwin.
>>
>> To test the idea, I made a small modification (patch attached) that is
>> *not* intended as a solution as it doesn't work for the general case,
>> but it does allow the tests to pass on Cygwin 64.
>
> I can confirm that Charles's patch, plus another one line patch
> to define CPU_SETSIZE, is enough to get Guile 3.0.x to build and run
> on my box.  All tests pass except strptime in French, and the absence
> of crypt.  This is a 64-bit build.

Mike, thanks for going further with the Guile build. The CPU_SETSIZE
issue was what was hanging me up from compiling before Andy's comment
got me to look at lightening. I assumed I had some configuration,
package, or compiler issue. Good to know there's a simple fix.

Just a further warning to anyone watching, that patch I posted is a
real hack job just to test my theory of the cause of the segfault. I
would expect it to fail when you have fewer than four arguments in a
JITed function call. I wouldn't try doing much else with that Guile
build besides run the tests. :)

--
Charles