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Re: What does this code print ?

From "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups comp.lang.c++
Subject Re: What does this code print ?
Date 2023-10-13 13:12 -0700
Organization A noiseless patient Spider
Message-ID <ugc8bo$3cv2m$1@dont-email.me> (permalink)
References <ug54sf$1ki2m$1@dont-email.me> <87lec95n0t.fsf@bsb.me.uk> <ugaeqo$2vefi$1@dont-email.me> <ugapal$31eim$1@dont-email.me> <20231013081459.652@kylheku.com>

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On 10/13/2023 9:34 AM, Kaz Kylheku wrote:
> On 2023-10-13, Bonita Montero <Bonita.Montero@gmail.com> wrote:
>> O.k., I'll explain it: the lambda is compiled twice for each cal-
> 
> I suspect the terminology you're groping for is "inlined".
> 
>> ling convention but in contrast to a generic lambda the thread
> 
> I don't believe it. It looks like the lambda uses the default calling
> convention ("__cdecl"), and is just being misused through the wrong
> calling convention.
> 
> It's possible that inlining will render this consideration
> moot, because if the function is inlined, then no actual calls are
> happening, and there are no calling conventions.
> (Compiling for a target other than x86 also renders it moot, since
> the calling convention extensions are ignored on x64 and arm.
> Let's assume they are there for a reason, and we are targetting x86).
> 
> Inlining is an optimization.
> 
> If your code depends on optimization (or lack thereof) in order to have
> the semantics you believe it to have, it's wrong.
> 
> If the function is actually called through the wrong conventions,
> there will be problems. The fastcall call will put the argument value in
> a register, whereas the stdcall function will try to take it from the
> stack, resulting in the callee accessing some value unrelated to the
> argument.
> 
> The stdcall might be able to access the argument value, but under
> stdcall, the callee is assumed to remove arguments from the stack
> which the cdecl callee will not do. That could leave the stack in
> sufficiently bad state that main is not able to return.
> 
> Or something; why go too deeply into guessing what incorrect code
> might be doing, if we're not actually fighting a fire.
> 
> That function inlining doesn't proliferate copies of static or
> thread_local variables isn't surprising at all; that's needed to
> preserve semantics.

Afaict, thread_local should be using the thread that is calling main in 
this example.

I should create a new thread for this, but:

Fwiw, actually, I am trying to understand how dtors are called wrt TLS 
when a thread is destroyed (aka, join returns) in C++. POSIX and C11 
makes this rather easy wrt:

Notice the dtor that we can use wrt (thread local storage) TLS:

https://en.cppreference.com/w/c/thread/tss_create

This is basically how POSIX does it via:

pthread_key_t
_______________
pthread_key_create
pthread_setspecific
pthread_getspecific
pthread_key_delete
_______________

Easy.

> 
> It is generic lambdas that stand in contrast. They are a macro-like
> mechanism which duplicates code, due to type inference or template
> argument deduction. They are also newer.
> 

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Thread

What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-11 05:30 +0200
  Re: What does this code print ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-11 14:03 +0100
    Re: What does this code print ? gazelle@shell.xmission.com (Kenny McCormack) - 2023-10-11 13:12 +0000
      Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-11 19:22 +0200
        Re: What does this code print ? scott@slp53.sl.home (Scott Lurndal) - 2023-10-11 17:41 +0000
          Re: What does this code print ? Bo Persson <bo@bo-persson.se> - 2023-10-11 20:24 +0200
          Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-13 05:24 +0200
            Re: What does this code print ? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-13 17:53 +0100
              Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-14 15:50 +0200
        Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-13 12:12 -0400
          Re: What does this code print ? scott@slp53.sl.home (Scott Lurndal) - 2023-10-13 17:27 +0000
          Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-14 15:52 +0200
            Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-14 11:26 -0400
              Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-15 09:08 +0200
                Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-15 12:55 -0700
                Re: What does this code print ? Richard Damon <news.x.richarddamon@xoxy.net> - 2023-10-15 22:19 -0400
                Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-18 20:58 -0700
    Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-11 19:21 +0200
    Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-11 12:41 -0700
      Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-11 12:43 -0700
      Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-13 05:25 +0200
    Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-12 20:50 -0700
      Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-13 08:50 +0200
        Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-13 12:15 -0400
          Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-14 15:53 +0200
            Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-14 11:26 -0400
              Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-15 09:00 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-15 13:15 -0400
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-17 07:47 +0200
                Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-17 11:34 -0700
        Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-13 16:34 +0000
          Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-13 13:12 -0700
            Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-14 02:36 +0000
              Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-13 20:44 -0700
              Re: What does this code print ? Paavo Helde <eesnimi@osa.pri.ee> - 2023-10-14 11:51 +0300
                Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-17 11:35 -0700
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-17 20:06 +0000
                Re: What does this code print ? Paavo Helde <eesnimi@osa.pri.ee> - 2023-10-18 11:43 +0300
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-18 17:29 +0000
                Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-18 11:31 -0700
                Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-19 14:43 -0700
          Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-14 15:54 +0200
            Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-14 18:05 +0000
              Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-14 14:58 -0400
              Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-15 08:58 +0200
        Re: What does this code print ? Richard Damon <news.x.richarddamon@xoxy.net> - 2023-10-14 12:47 -0400
          Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-15 09:07 +0200
            Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-15 09:12 +0200
              Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-15 09:16 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-15 13:35 -0400
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-17 07:48 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-17 23:04 -0400
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-19 19:58 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-19 14:39 -0400
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-19 19:58 +0200
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-19 18:06 +0000
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-19 20:11 +0200
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-19 19:20 +0000
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-19 16:06 -0400
                Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-19 14:45 -0700
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-19 23:26 +0000
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-20 09:19 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-20 05:47 -0400
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-20 17:59 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-20 19:16 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-21 08:02 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-21 08:38 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-21 19:40 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-21 10:54 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-21 20:34 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-21 12:45 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-22 04:18 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-21 19:28 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-22 06:53 +0200
                Re: What does this code print ? Branimir Maksimovic <branimir.maksimovic@icloud.com> - 2023-10-22 09:59 +0000
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-22 07:12 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-23 19:05 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-23 10:40 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-24 16:03 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-24 07:28 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-24 17:01 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-24 08:28 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-24 18:27 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-24 10:05 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-24 19:08 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-24 10:39 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-24 20:25 +0200
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-24 19:48 +0000
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-25 10:54 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-25 08:43 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-25 17:57 +0200
                Re: What does this code print ? Branimir Maksimovic <branimir.maksimovic@icloud.com> - 2023-10-24 16:40 +0000
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-24 19:07 +0200
                Re: What does this code print ? scott@slp53.sl.home (Scott Lurndal) - 2023-10-24 15:25 +0000
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-24 08:34 -0700
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-24 16:34 +0000
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-24 19:05 +0200
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-20 14:50 +0000
                Re: What does this code print ? Bo Persson <bo@bo-persson.se> - 2023-10-20 17:34 +0200
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-20 15:59 +0000
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-20 18:00 +0200
                Re: What does this code print ? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-20 16:06 +0000
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-20 18:40 +0200
                Re: What does this code print ? gazelle@shell.xmission.com (Kenny McCormack) - 2023-10-20 20:07 +0000
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-21 08:04 +0200
              Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-15 13:35 -0400
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-17 07:50 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-17 23:08 -0400
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-19 20:02 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-19 14:43 -0400
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-19 20:02 +0200
            Re: What does this code print ? scott@slp53.sl.home (Scott Lurndal) - 2023-10-15 14:36 +0000
              Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-15 18:15 +0200
                Re: What does this code print ? Richard Damon <news.x.richarddamon@xoxy.net> - 2023-10-15 22:23 -0400
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-17 07:51 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-17 23:08 -0400
            Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-15 13:25 -0400
        Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-14 11:33 -0700
          Re: What does this code print ? Paavo Helde <eesnimi@osa.pri.ee> - 2023-10-14 21:54 +0300
            Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-14 11:56 -0700
            Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-24 15:53 -0700
              Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-25 15:07 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-25 08:43 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-25 18:01 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-25 09:21 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-25 18:24 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-25 11:23 -0700
                Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-25 15:02 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-26 07:13 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-25 23:09 -0700
                Re: What does this code print ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-10-25 23:55 -0400
                Re: What does this code print ? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-25 15:01 -0700
                Re: What does this code print ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-10-26 07:15 +0200
                Re: What does this code print ? Richard Damon <richard@damon-family.org> - 2023-10-25 23:12 -0700

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