Wine Traffic #36 For 27 Mar 2000
Table Of Contents
This is the 36th release of the Wine's kernel cousin
publication. It's main goal is to distribute widely what's
going on around Wine (the Un*x windows emulator).
Wine 20000326 has been released. Announce reads:
- More DLLs separated from the Wine core.
- Debugger rewritten to use Win32 debugging API.
- Many improvements to WINASPI support.
- New WineMine application.
- Lots of bug fixes.
Mailing List Stats For This Week
We looked at 129 posts in 650K.
There were 39 different contributors.
24 posted more than once.
21 posted last week too.
The top posters of the week were:
- 10 posts in 204K by Patrik Stridvall <firstname.lastname@example.org>
- 8 posts in 22K by Ulrich Weigand <email@example.com>
- 8 posts in 22K by Ove Kaaven <firstname.lastname@example.org>
- 7 posts in 16K by Alexandre Julliard <email@example.com>
- 7 posts in 14K by Uwe Bonnes <firstname.lastname@example.org>
- Full Stats
Wine's resource compiler
Archive Link: "PrgWin95: Extern and #pragma/#line/#error support"
Bertho Stultiens, Dimitrie Paun, Francois Gouget, , Uwe Bonnes, Patrik Stridvall, Marcus Meissner
While continuing his effort to test the Petzold's Windows Programming
samples (see this issue),
Francois Gouget sent a patch to correct a few issues in wrc - the
Wine's resource compiler -. Those fixes mainly dealt with some
uncorrectly supported preprocessor directives (like
#line or #pragma)
Bertho Stultiens (the author of wrc) explained:
The problem is that wrc has a semantical preprocessor instead of a
lexical preprocessor. There are quite a few other constructs that also
fail in wrc. I have been working on a new preprocessor for the past two
months (and it is working), but it is not yet completely done. Main
problem is that I need to rewrite the macro-expansion code for nested
macros (to prevent functional recursion) and definitely speed it up
because it takes 3.5 seconds to compile some files (oh well, it does
20000 lines per second though; almost as fast as gcc:-). My coming
changes also correct the other 2 major issues: filenames and usertype
Dimi Paun started then a long thread by asking whether if it was worth
creating Wine's own preprocessor embedded inside wrc, instead of using
gcc as a preprocessor.
Marcus Meissner and Patrik Stridvall pointed out that gcc's
preprocessor wasn't available on all platforms, but that configure
could look at any decent preprocessor, like plain cpp. Uwe Bonnes and
Patrik Stridvall also noted some discrepancies between gcc's
preprocessor and cpp - like some different command line options
handling, but also, a different handling of the "\r\n" sequence as a
resource file terminator -, but Patrik was confident that those
"features" could be circumvented. He demonstrated it by sending a
patch which allowed to compile resource files on Solaris (which was
working with both cpp and gcc as preprocessors).
Some people (like Uwe Bonnes and Patrik Stridvall) remarked that using
plumbing (feeding wrc's input with a preprocessor output) ended up
with poor error reporting to the end user.
But Dimi went further:
the point is that rewriting and
reinvention of the wheel for the single purpose that it is more
convenient to have it included in wine is a bit silly. We require a C
compiler (for now we require gcc with is OK IMO), we require a make
program (don't know if gmake is required though), perl, yacc, lex,
etc. It would be simply silly to reimplement all this programs simply
because some systems don't have them. They are free on the net,
download them., and asked Bertho if he agreed to strip the
preprocessor part from wrc.
Bertho had a rather different opinion:
and he went on explaining with more details the changes underway
Well, a good question. Stripping the preprocessor could be an advantage
if it was solely used with wine. But, this is not the case. There have
been other uses of wrc which require the preprocessor built in.
To make it short [ahum;-];
I intended wrc to be versatile enough to be used both within wine
(because we lacked a real resource-compiler back then) and powerful
enough to be used within other projects which have nothing to do with
wine, but want to use windows-resources (for whatever reason). The
wine-license made this a perfect option and I kinda liked it too.
So, keeping that in mind, the whole discussion is a bit artificial and
not changing my work nor my attitude in putting a real preprocessor into
wrc's frontend. This will be entirely optional for use and a
command-line option can be used to bypass it.
Even if Alexandre would want to reject the upcoming patches (which I do
not think he will), then it would still not change my attitude because
the changes will be published by other means. Solely because I feel that
wrc should be capable of compiling resources in a stand-alone manner and
no one should be required more than wrc to get resources compiled.
A good bunch of posters approved Bertho's approach, and Francois
Gouget shed some more light
Yes, wrc will be faster. That is actually the primary technical reason
for me to split wrc into a preprocessor/compiler combination. The
current mix (a bad hack) was there to help out for the time being. The
extra rules in the scanner and parser make it awfully complex to
change anything of substance in any part. This is why user-resources
and filenames are wrong. I could not get this put into the current
design without making an even worse hack.
Wrc's backend will be cleaned up so it will understand enough C and C++
constructs so that they can be filtered out and for the rest it will be
a 'clean' and 'compatible' compiler. All lexical substitutions (i.e. the
preprocessor) will be done in the frontend. Whether you choose to use it
is not my primary concern.
Then for reinventing the wheel. Yes, many have done it before. But, do
you know a full-working preprocessor in the public domain that can be
put into wrc without problems? I don't. The rest I know is GPL.
As a conclusion, wrc will keep its integrated preprocessor (keep
posted for the day where Bertho releases the new wrc version).
I would like to point out that even if you use gcc as the
pre-processor, as I did, wrc must still be aware of some directives
like '# <line> <file> and '#pragma'. I seemed to me that this was not
always clear in the messages.
We need to handle '# <line> <file>
- because it's generated by the preprocessor and thus obviously
present in the pre-processor's output although this can be disabled
- because if we don't then we have no idea about the line/file
the error occurred in and the messages are thus hard to understand (hint:
preprocess to a file and then run wrc on that file)
We need to support the '#pragma'
- because since they are intended to be used by the compiler they will
always be there. Foretunately all we have to do is ignore them
Wine and XFree 4.0
Archive Link: "Wine problem with XFree 4.0"
Jeremy White, Ove Kaaven, Alexandre Julliard, Ulrich Weigand, Andrew Lewycky, , Ove Kåven
Following post from last week
regarding the incompatibilities between Wine and XFree 4.0, Jeremy
White reopened an old discussion on pthread support in Wine:
Jeremy also asked why Ove's patch never made its way inside the Wine's
Ove Kåven gave some more indication on his work:
I tried to understand exactly what the problem was if we linked Wine
with X 4.0, libpthread, and OpenGL. Really, the core issue is why we
can't link in libpthread.
To rehash what is already known:
After a scan of the glibc 2.1 source code (and no experimental
evidence whatsoever), I found only the following two problems:
malloc and free will fail badly: I see two
issues. First, the code for malloc tests to see if
__pthread_initialize is available. If so, it invokes it. I believe
that __pthread_initialize will actually run correctly, and start the
pthread_manager. I have no proof of this. Second, as malloc and free
manipulate internal structures, they rely on macros from
malloc-t.h. The ones I inspected were mutex_init, mutex_lock,
et. all. Basically, if libpthread is linked in, and the weak symbols
for __pthread_mutex_xxx are available, then malloc will use them,
otherwise they turn into NOPs (and malloc is presumably running in a
single thread environment).
However, in our case, the code for pthread_mutex_lock will be
invoked. That code, in turn, grabs the pthread_self descriptor from
the GS register. Of course, we're not really a pthread and boom down
errno will fail: Again, same basic issue.
However, I found no further instances where glibc examines the weak
aliasing on the pthread functions. Of course, I did not look at the
source code for X 4.0 or any other library to see in what ways it
depends on the weak aliasing of pthreads.
As I understand Ove's pthread patch, his patch resolves this problem.
I don't have his patch in front of me, but I believe he did this by
registering Wine threads with libpthread (setting up the GS register),
and by correspondingly trapping the creation of threads from
libpthread and registering them with Wine.
and regarding the rejection cause:
My original pthread patch defined only the __pthread_xxx routines that
glibc used, so that libc would use them instead of assuming a
single-thread environment, since wine IS multithreaded.
pthread was normally never linked in before XFree86 4.0 appeared, so when
it did, I had to update the patch to also define standard pthread symbols
to override pthread's own (libwine is before pthread-using X11 libs on the
link command line...)
The OpenGL and MT parts of XFree86 4.0 uses pthreads directly, without
going through any weak aliases. In other words, they explicitly link
I just implemented the pthread primitives on top of Win32 synchronization
primitives. For example, pthread_mutex_init() is a wrapper for
InitializeCriticalSection(), pthread_mutex_lock() is a wrapper for
it is currently
quite glibc-specific (Alexandre calls in un-portable, although I
wouldn't myself consider it impossible to port to other systems, like
FreeBSD), and Alexandre really wants to see a portable fix for libc
threadsafety before slipping in system-specific workarounds that ~90%
of the developers would consider "good enough" (and the rest wouldn't
know how to fix).
Alexandre Julliard jumped in:
Ulrich Weigand raised some more problematic points:
the theory is that if it's broken for everybody, it's more likely to
get fixed than if it only breaks on "exotic" platforms. Since it still
hasn't been fixed it seems I'll have to revise my theory...
I think at this point we have two possibilities: one is to provide our
own complete libpthread implementation to override the libc one,
i.e. the extended version of Ove's patch.
The other solution is to try to use the existing libpthread to create
our threads; if we can work around the %gs register problem, this
would have the advantage of better integrating with the native
libraries (for instance gdb would then be able to understand what's
going on with threads). This is IMO a more elegant solution, but the
big question is: can it be made to work?
The first item fools Wine's manipulation of the LDT (Wine as
libpthread thinks he's the only one tweaking the LDT entries), and
puts a hard constraint (%gs register shall not be touched, which is
something emulated Windows's program don't ensure).
One possible solution to directly use pthreads would be to:
- libpthread sets up its own segments and stores selectors to
them in %gs
- libpthread uses the current stack pointer to determine the
Actually, I'm not sure whether any version of libpthread uses both
those constructs at the same time (as both are used to determine the
current thread), but I've seen (different) versions that use either one.
One possible solution to remove the restrictions on Win32 apps would be
to treat Win32 apps the same way as Win16 apps, using explicit transition
thunks. That way, we could switch from the pthreads stack to the Wine
stack, and could save/restore %gs as well ... Furthermore, this approach
would also allow to use compilers that don't support stdcall, and it might
simplify a processor emulator version of Wine. On the other hand, there's
quite a bit of overhead on every transition :-/
Alex Korobka also pointed out that pthread was missing the
suspend/resume feature needed to implement the ThreadSuspend(),
ThreadResume() API calls.
Andrew Lewycky reported:
I have a patch that runs wine
on pthreads in glibc 2.1, that works for 32-bit programs at least. I
didn't bother with the LDT or %gs stuff since linuxthreads-0.8 does
not use it, due to bugs in the 2.0 kernels. (So it may come back some day.)
, which gave some good hope on being able to use pthread, but
also brings lots of issues, as Ulrich already pointed out: the
different libpthread version use different mechanisms to identify a
thread (%gs, stack...), opening various concerns from all the
Ulrich and Andrew then discussed some other concerns with libpthread
while executing the exception handlers (which also have issues with
identifying the current thread).
As of today, no global solution has been reached so far.
Sharon And Joy