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Re: Can extern "C" functions throw exceptions

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"james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> writes:

> On Wednesday, October 6, 2021 at 4:12:52 PM UTC-4, Tim Rentsch wrote:
>
>> James Kuyper <james...@alumni.caltech.edu> writes:
>>
>>> On 9/12/21 9:44 AM, Chris Vine wrote:
>
> ...
>
>>>> For functions, it does more than affecting naming.  The language
>>>> linkage of a function determines two things:  the function's name
>>>> (name mangling) and the function's type (calling convention).
>>>
>>> Furthermore, and not widely appreciated, those two aspects are
>>> separable by using a typedef for a function's type.  The language
>>> linkage of the typedef determines the calling convention, while the
>>> language linkage of the function itself determines the name
>>> mangling.
>>
>> Can you illustrate how that would be done?  Since the language
>> linkage of a function is part of its type, it sounds like trying
>> to do such a thing would inevitably lead to undefined behavior.
>
> The language linkage of a function's type is indeed part of that type.  The
> language linkage of a function's name is not.  The standard's description of
> language linkage in 9.11p1 starts with the sentence "All function types,
> function names with external linkage, and variable names with external
> linkage have a language linkage.", clearly making the point that the
> language linkage of a function's type is a distinct thing from the language
> linkage of a function's name.  The standard could have inextricably linked
> them together - but it does not.  In fact, 9.11p5 includes an example
> demonstrating how they can be separated:
>
>     extern "C" typedef void FUNC();
>     FUNC f2;  // the name f2 has C ++ language linkage and the
>                      // function?s type has C language linkage
>
> [...]

Thank you for this citation.  It doesn't answer all my questions
but it certainly does provide an illuminating example.

It appears, however, that in practice there is no difference
between a type with a C language linkage and a C++ language
linkage.  Apparently most compilers ignore the distinction
because following the rules would break too much code.  Here
is a link to stackoverflow with more information:

    https://stackoverflow.com/questions/26647259/
            is-extern-c-a-part-of-the-type-of-a-function

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Can extern "C" functions throw exceptions Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-11 12:35 +0200
  Re: Can extern "C" functions throw exceptions Bo Persson <bo@bo-persson.se> - 2021-09-11 13:49 +0200
    Re: Can extern "C" functions throw exceptions "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2021-09-11 13:57 +0200
    Re: Can extern "C" functions throw exceptions Paavo Helde <myfirstname@osa.pri.ee> - 2021-09-11 15:19 +0300
    Re: Can extern "C" functions throw exceptions Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-11 15:32 +0200
    Re: Can extern "C" functions throw exceptions HorseyWorsey@the_stables.com - 2021-09-11 15:54 +0000
  Re: Can extern "C" functions throw exceptions "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2021-09-11 13:55 +0200
    Re: Can extern "C" functions throw exceptions Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-11 15:34 +0200
      Re: Can extern "C" functions throw exceptions Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-11 15:58 +0200
      Re: Can extern "C" functions throw exceptions "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2021-09-11 17:00 +0200
        Re: Can extern "C" functions throw exceptions "daniel...@gmail.com" <danielaparker@gmail.com> - 2021-10-06 13:36 -0700
          Re: Can extern "C" functions throw exceptions Branimir Maksimovic <branimir.maksimovic@icloud.com> - 2021-10-06 20:42 +0000
            Re: Can extern "C" functions throw exceptions Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-10-06 16:12 -0700
              Re: Can extern "C" functions throw exceptions Branimir Maksimovic <branimir.maksimovic@icloud.com> - 2021-10-06 23:22 +0000
                Re: Can extern "C" functions throw exceptions Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-10-06 17:03 -0700
    Re: Can extern "C" functions throw exceptions HorseyWorsey@the_stables.com - 2021-09-11 15:56 +0000
    Re: Can extern "C" functions throw exceptions David Brown <david.brown@hesbynett.no> - 2021-09-11 20:10 +0200
      Re: Can extern "C" functions throw exceptions Juha Nieminen <nospam@thanks.invalid> - 2021-09-12 09:20 +0000
        Re: Can extern "C" functions throw exceptions Paavo Helde <myfirstname@osa.pri.ee> - 2021-09-12 12:34 +0300
        Re: Can extern "C" functions throw exceptions David Brown <david.brown@hesbynett.no> - 2021-09-12 12:24 +0200
          Re: Can extern "C" functions throw exceptions Bonita Montero <Bonita.Montero@gmail.com> - 2021-09-12 12:29 +0200
        Re: Can extern "C" functions throw exceptions Chris Vine <chris@cvine--nospam--.freeserve.co.uk> - 2021-09-12 14:44 +0100
          Re: Can extern "C" functions throw exceptions James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-09-12 23:13 -0400
            Re: Can extern "C" functions throw exceptions David Brown <david.brown@hesbynett.no> - 2021-09-13 09:30 +0200
            Re: Can extern "C" functions throw exceptions Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-10-06 13:12 -0700
              Re: Can extern "C" functions throw exceptions "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2021-10-07 07:09 -0700
                Re: Can extern "C" functions throw exceptions Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-14 15:21 -0800
                Re: Can extern "C" functions throw exceptions Richard Damon <Richard@Damon-Family.org> - 2021-12-14 21:17 -0500
                Re: Can extern "C" functions throw exceptions Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-16 04:21 -0800
                Re: Can extern "C" functions throw exceptions "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2021-12-14 19:06 -0800
                Re: Can extern "C" functions throw exceptions Ian Collins <ian-news@hotmail.com> - 2021-12-16 13:14 +1300
                Re: Can extern "C" functions throw exceptions "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-12-15 18:05 -0800
                Re: Can extern "C" functions throw exceptions Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-16 04:37 -0800
                Re: Can extern "C" functions throw exceptions Ian Collins <ian-news@hotmail.com> - 2021-12-17 09:39 +1300
                Re: Can extern "C" functions throw exceptions Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-16 19:24 -0800
                Re: Can extern "C" functions throw exceptions Tim Rentsch <tr.17687@z991.linuxsc.com> - 2021-12-16 04:29 -0800
          Re: Can extern "C" functions throw exceptions Juha Nieminen <nospam@thanks.invalid> - 2021-09-13 05:34 +0000
            Re: Can extern "C" functions throw exceptions Paavo Helde <myfirstname@osa.pri.ee> - 2021-09-13 09:55 +0300
  Re: Can extern "C" functions throw exceptions Paavo Helde <myfirstname@osa.pri.ee> - 2021-09-11 15:12 +0300
  Re: Can extern "C" functions throw exceptions red floyd <no.spam.here@its.invalid> - 2021-09-13 13:21 -0700

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