Re: Request Assistance Calling D from C++: weird visibility issue inside struct and namespace

2017-11-08 Thread Andrew Edwards via Digitalmars-d-learn
On Wednesday, 8 November 2017 at 08:42:01 UTC, Petar Kirov 
[ZombineDev] wrote:


Walter has recently been working on improving the C++ mangling, 
so be sure to test the latest dmd nightly build and if that 
doesn't work be sure to file bug report(s).


https://github.com/dlang/dmd/pull/7250
https://github.com/dlang/dmd/pull/7259
https://github.com/dlang/dmd/pull/7272


Done: https://issues.dlang.org/show_bug.cgi?id=17975


Re: Request Assistance Calling D from C++: weird visibility issue inside struct and namespace

2017-11-08 Thread Andrew Edwards via Digitalmars-d-learn

On Wednesday, 8 November 2017 at 15:12:05 UTC, MGW wrote:

The useful material.
https://www.youtube.com/watch?v=HTgJaRRfLPk


Useful indeed, thank you.


Re: Request Assistance Calling D from C++: weird visibility issue inside struct and namespace

2017-11-08 Thread MGW via Digitalmars-d-learn
On Wednesday, 8 November 2017 at 06:34:27 UTC, Andrew Edwards 
wrote:
I'm having a little bit of problem calling D code from C++ and 
would appreciate some assistance. First, given the following 
C++ program wich compiles, links, and runs without any problem:


The useful material.
https://www.youtube.com/watch?v=HTgJaRRfLPk


Re: Request Assistance Calling D from C++: weird visibility issue inside struct and namespace

2017-11-08 Thread Petar via Digitalmars-d-learn
On Wednesday, 8 November 2017 at 07:55:02 UTC, Andrew Edwards 
wrote:

On Wednesday, 8 November 2017 at 07:30:34 UTC, evilrat wrote:

On Wednesday, 8 November 2017 at 06:34:27 UTC, Andrew Edwards

just using fully qualified name didn't make it?

void call_cpp() {
::foo("do great things"); // calling global foo
return;
}



No, it did not.


Are you sure you put it in a namespace in C++ too?


Yes. That wasn't the issue

otherwise there might be some name mangling incompatibility 
that probably worth filling a bug report


That's the one. Thanks to the hint form, Nicholas Wilson, I was 
able to track it down and resolve it with a call to 
pragma(mangle).


-Andrew


Walter has recently been working on improving the C++ mangling, 
so be sure to test the latest dmd nightly build and if that 
doesn't work be sure to file bug report(s).


https://github.com/dlang/dmd/pull/7250
https://github.com/dlang/dmd/pull/7259
https://github.com/dlang/dmd/pull/7272


Re: Request Assistance Calling D from C++: weird visibility issue inside struct and namespace

2017-11-08 Thread Andrew Edwards via Digitalmars-d-learn

On Wednesday, 8 November 2017 at 07:30:34 UTC, evilrat wrote:

On Wednesday, 8 November 2017 at 06:34:27 UTC, Andrew Edwards

just using fully qualified name didn't make it?

void call_cpp() {
::foo("do great things"); // calling global foo
return;
}



No, it did not.


Are you sure you put it in a namespace in C++ too?


Yes. That wasn't the issue

otherwise there might be some name mangling incompatibility 
that probably worth filling a bug report


That's the one. Thanks to the hint form, Nicholas Wilson, I was 
able to track it down and resolve it with a call to 
pragma(mangle).


-Andrew


Re: Request Assistance Calling D from C++: weird visibility issue inside struct and namespace

2017-11-07 Thread Andrew Edwards via Digitalmars-d-learn
On Wednesday, 8 November 2017 at 07:06:39 UTC, Nicholas Wilson 
wrote:
On Wednesday, 8 November 2017 at 06:34:27 UTC, Andrew Edwards 
wrote:
I'm having a little bit of problem calling D code from C++ and 
would appreciate some assistance. First, given the following 
C++ program wich compiles, links, and runs without any problem:


Try using `nm` on the C++ object to find out what it thinks the 
mangling should be.

Check that against the mangling DMD produces.


Tried it, and it works.

Solution:

nm dexample | grep foo -> returns the __C++__mangling

Use it to define the function as such:

pragma(mangle, "__C++__mangling")
extern (C++) void foo(const char* str) {
// doing great things;
}

Thank you so much.

-Andrew



Re: Request Assistance Calling D from C++: weird visibility issue inside struct and namespace

2017-11-07 Thread evilrat via Digitalmars-d-learn
On Wednesday, 8 November 2017 at 06:34:27 UTC, Andrew Edwards 
wrote:


Modify example.cpp to:

==
// example.cpp
#include "example.h"
namespace SomeApi {}
struct SomeStruct {}
void call_cpp() {
foo("do great things");
return;
}
==




Compile and link and you have D program calling, calling C++, 
which in turn calls D.


My problem is that I've encountered an issue where this does 
not work: when the function is being called from a namespace or 
local scope in C++, the linker cannot find the definition. For 
example:




just using fully qualified name didn't make it?

void call_cpp() {
::foo("do great things"); // calling global foo
return;
}



In a last-ditch effort, I placed all of these definitions into 
dexample.d and, it compiled, but still filed to linking:




Are you sure you put it in a namespace in C++ too?

otherwise there might be some name mangling incompatibility that 
probably worth filling a bug report




Re: Request Assistance Calling D from C++: weird visibility issue inside struct and namespace

2017-11-07 Thread Nicholas Wilson via Digitalmars-d-learn
On Wednesday, 8 November 2017 at 06:34:27 UTC, Andrew Edwards 
wrote:
I'm having a little bit of problem calling D code from C++ and 
would appreciate some assistance. First, given the following 
C++ program wich compiles, links, and runs without any problem:


Try using `nm` on the C++ object to find out what it thinks the 
mangling should be.

Check that against the mangling DMD produces.