[Issue 16650] Wrong mangling for extern(C++) with posix stat_t
https://issues.dlang.org/show_bug.cgi?id=16650 Jacob Carlborg changed: What|Removed |Added CC||d...@me.com --- Comment #1 from Jacob Carlborg --- 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. --
[Issue 16650] Wrong mangling for extern(C++) with posix stat_t
https://issues.dlang.org/show_bug.cgi?id=16650
Vladimir Panteleev changed:
What|Removed |Added
Status|NEW |RESOLVED
Resolution|--- |INVALID
--- Comment #2 from Vladimir Panteleev ---
(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.
--
[Issue 16650] Wrong mangling for extern(C++) with posix stat_t
https://issues.dlang.org/show_bug.cgi?id=16650 Vladimir Panteleev changed: What|Removed |Added Keywords||C++ Hardware|x86_64 |All --
[Issue 16650] Wrong mangling for extern(C++) with posix stat_t
https://issues.dlang.org/show_bug.cgi?id=16650 --- Comment #3 from Jacob Carlborg --- Is it possible to use pragman(mangle) on a struct? --
[Issue 16650] Wrong mangling for extern(C++) with posix stat_t
https://issues.dlang.org/show_bug.cgi?id=16650
--- Comment #4 from Vladimir Panteleev ---
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.
--
[Issue 16650] Wrong mangling for extern(C++) with posix stat_t
https://issues.dlang.org/show_bug.cgi?id=16650
--- Comment #5 from Jacob Carlborg ---
(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?
--
[Issue 16650] Wrong mangling for extern(C++) with posix stat_t
https://issues.dlang.org/show_bug.cgi?id=16650 --- Comment #6 from Vladimir Panteleev --- (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. --
