[Issue 15843] D-type mangling used for extern(C) (extern) function declaration inside function body, on LDC, GDC, and DMD.

Oct 26, 2017

Walter Bright

Jan 16, 2022

Basile-z

Jan 16, 2022

Jan 16, 2022

Jan 16, 2022

Jan 17, 2022

Jan 17, 2022

Dec 17, 2022

Oct 03

https://issues.dlang.org/show_bug.cgi?id=15843 Walter Bright <bugzilla@digitalmars.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Keywords| |mangling CC| |bugzilla@digitalmars.com --

https://issues.dlang.org/show_bug.cgi?id=15843 Iain Buclaw <ibuclaw@gdcproject.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |ibuclaw@gdcproject.org --- Comment #1 from Iain Buclaw <ibuclaw@gdcproject.org> --- I would err on the side of this is working as intended. Nested functions are not compatible with C, and so should not have a C name (by declaring the function inside main, it implicitly gets a "this" context parameter) --

https://issues.dlang.org/show_bug.cgi?id=15843 Basile-z <b2.temp@gmx.com> changed: What |Removed |Added ---------------------------------------------------------------------------- See Also| |https://issues.dlang.org/sh | |ow_bug.cgi?id=22682 --

https://issues.dlang.org/show_bug.cgi?id=15843 Mathias LANG <pro.mathias.lang@gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |pro.mathias.lang@gmail.com --- Comment #2 from Mathias LANG <pro.mathias.lang@gmail.com> --- Perhaps we should error out on `extern` and `extern(XXX)` functions then? --

https://issues.dlang.org/show_bug.cgi?id=15843 --- Comment #3 from anonymous4 <dfj1esp02@sneakemail.com> --- Static nested functions with C calling convention are useful as system callbacks. They just don't need to be visible to other linked modules. --

January 17, 2022

[Issue 15843] D-type mangling used for extern(C) (extern) function declaration inside function body, on LDC, GDC, and DMD.

Posted by Steven Schveighoffer

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Steven Schveighoffer

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https://issues.dlang.org/show_bug.cgi?id=15843

Steven Schveighoffer <schveiguy@gmail.com> changed:

           What    |Removed                     |Added
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                 CC|                            |schveiguy@gmail.com

--- Comment #4 from Steven Schveighoffer <schveiguy@gmail.com> ---
extern(C) specifies not only the mangling, but also the calling convention. So having extern(C) inner functions do serve a purpose. I think the mangling is really implementation defined, since C doesn't have any notion of inner functions.

Note that `extern` on its own isn't doing anything here.

If anything, I'd say pragma(mangle) should work in this context, that would at
least give a more straightforward path (really issue 22682).

Note that defining the prototype without `static` indeed suggests it should have a `this` pointer, but it doesn't work even if you add `static`.

--

https://issues.dlang.org/show_bug.cgi?id=15843 basile-z <b2.temp@gmx.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED Resolution|--- |FIXED --- Comment #5 from basile-z <b2.temp@gmx.com> --- Prgma mangle works locally since a year or so: ``` void main() { pragma(mangle, "func") extern(C) int func(int); static assert(func.mangleof == "func"); } ``` --

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