https://issues.dlang.org/show_bug.cgi?id=16650

Jacob Carlborg <doob@me.com> changed:

           What    |Removed                     |Added
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                 CC|                            |doob@me.com

--- Comment #1 from Jacob Carlborg <doob@me.com> ---
I don't think it's the mangling that is wrong. Rather it's the declaration of the struct. Not sure why it's called "stat_t" in the D version when it's called "stat" in the C headers.

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https://issues.dlang.org/show_bug.cgi?id=16650

Vladimir Panteleev <dlang-bugzilla@thecybershadow.net> changed:

           What    |Removed                     |Added
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             Status|NEW                         |RESOLVED
         Resolution|---                         |INVALID

--- Comment #2 from Vladimir Panteleev <dlang-bugzilla@thecybershadow.net> ---
(In reply to Jacob Carlborg from comment #1)
> Not sure why it's called "stat_t" in the D version when it's called "stat" in the C headers.

It's because in C, "stat" is both the name of a struct and a function. This is not a problem for C because structs in C have their own namespace (unless you typedef them), but there is no equivalent in D.

There are some workarounds available:

- You can use extern(C) to link the D declaration with the C definition. As
argument types are not mangled with C linkage, type name mismatches will not
result in a link error.
- You can use pragma(mangle) on the D side to directly override a function's
mangled name;
- Finally, on the D side you could declare the function as:

struct stat;
void myFunc(stat*){}

then cast the stat_t* to stat* when invoking the function.

As this is not a bug in D and simple workarounds exist, I'll close this, but feel free to reopen if you can present actionable ideas for improving the situation.

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https://issues.dlang.org/show_bug.cgi?id=16650

Vladimir Panteleev <dlang-bugzilla@thecybershadow.net> changed:

           What    |Removed                     |Added
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           Keywords|                            |C++
           Hardware|x86_64                      |All

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https://issues.dlang.org/show_bug.cgi?id=16650

--- Comment #3 from Jacob Carlborg <doob@me.com> ---
Is it possible to use pragman(mangle) on a struct?

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https://issues.dlang.org/show_bug.cgi?id=16650

--- Comment #4 from Vladimir Panteleev <dlang-bugzilla@thecybershadow.net> ---
It's easy enough to test!

$ cat test.d
pragma(mangle, "CeciNestPasUnS")
struct S { }

extern(C++) void fun(S* s);

pragma(msg, fun.mangleof);

$ dmd -o- test.d
_Z3funP1S

Looks like pragma(mangle) has no effect on structs so far.

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https://issues.dlang.org/show_bug.cgi?id=16650

--- Comment #5 from Jacob Carlborg <doob@me.com> ---
(In reply to Vladimir Panteleev from comment #4)
> It's easy enough to test!
> 
> $ cat test.d
> pragma(mangle, "CeciNestPasUnS")
> struct S { }
> 
> extern(C++) void fun(S* s);
> 
> pragma(msg, fun.mangleof);
> 
> $ dmd -o- test.d
> _Z3funP1S
> 
> Looks like pragma(mangle) has no effect on structs so far.

I didn't really expect it to work. Perhaps a worthwhile feature?

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https://issues.dlang.org/show_bug.cgi?id=16650

--- Comment #6 from Vladimir Panteleev <dlang-bugzilla@thecybershadow.net> ---
(In reply to Jacob Carlborg from comment #5)
> I didn't really expect it to work. Perhaps a worthwhile feature?

Perhaps! Feel free to file an enhancement request.

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