Make error about opencvjs HOT 8 OPEN

I also got same error using Emscripten 1.37.16 and OpenCV 3.1.0, using master branch of opencvjs. After opening bind.h, I found that the template base only accepts single argument indeed. When I removed the boolean value in bindings.cpp, I got this error instead:

In file included from ../../bindings.cpp:47:
/home/leben/Labs/emsdk-portable/emscripten/1.37.16/system/include/emscripten/bind.h:1065:20: error: cannot cast 'cv::Algorithm *' to 'cv::Feature2D *' via virtual base 'cv::Algorithm'
            return static_cast<To*>(ptr);
                   ^~~~~~~~~~~~~~~~~~~~~
/home/leben/Labs/emsdk-portable/emscripten/1.37.16/system/include/emscripten/bind.h:1060:21: note: in instantiation of function template specialization
      'emscripten::base<cv::Algorithm>::convertPointer<cv::Algorithm, cv::Feature2D>' requested here
            return &convertPointer<BaseClass, ClassType>;
                    ^
/home/leben/Labs/emsdk-portable/emscripten/1.37.16/system/include/emscripten/bind.h:1125:53: note: in instantiation of function template specialization
      'emscripten::base<cv::Algorithm>::getDowncaster<cv::Feature2D>' requested here
            auto downcast = BaseSpecifier::template getDowncaster<ClassType>();
                                                    ^
../../bindings.cpp:3271:5: note: in instantiation of member function 'emscripten::class_<cv::Feature2D, emscripten::base<cv::Algorithm> >::class_' requested here
    emscripten::class_<cv::Feature2D ,base<Algorithm>>("Feature2D")
    ^
1 error generated.
ERROR:root:compiler frontend failed to generate LLVM bitcode, halting
Traceback (most recent call last):
  File "make.py", line 183, in <module>
    emscripten.Building.emcc('../../bindings.cpp', emcc_binding_args, 'bindings.bc')
  File "/home/leben/Labs/emsdk-portable/emscripten/1.37.16/tools/shared.py", line 1996, in emcc
    assert os.path.exists(output_filename), 'emcc could not create output file: ' + output_filename
AssertionError: emcc could not create output file: bindings.bc

Still trying to figure it out. Any help would be appreciated.

from opencvjs.

Same problem here... Any suggestions?

from opencvjs.

It turns this is due to non-successful application of the emscripten patch delivered within this repository.

Working on windows, I moreover had to disable multiprocessing and modify class FakeMultiprocessor (to support map_async) in emscripten\incoming\tools\shared.py for reasons I do not understand. Finally it worked out.

from opencvjs.

I applied the emscripten patch but still run into this issue.

from opencvjs.

Do you have the issue of the first or the second post? The issue of the first post should be fixed by the patch. The issue of the second post only appears if you modify bindings.cpp erroneously.

from opencvjs.

Sorry, I am referring to the error caused by the inner template argument in feature2d. I applied the patch and rebuild emsdk as suggested. Do I have to modify the bindings to get it running?

from opencvjs.

I'm not an expert in this, but I believe the patch didn't work.
The error you get complains about too many template arguments of base template.
The patch changes the number of arguments of the base template to 2, so it should then work.

Have a look inside the diff file, it's quite obvious.
I did actually not manage to apply the patch (on Windows) and made the changes listed inside the diff file manually, instead.

from opencvjs.

@drhouse82
Hello there, im new of this, and have same error on windows.
seems like your reply is only answer who make successfuly on window in this project.
but sadly, im newbie at programming, therefore i cannot understand what is ovbious, what line do i edit or else.
Please, can you describe little more detail?
this will help me and other people who trying to use this project in future.
cause no one give answer actually working so far guess..

Thanks.

from opencvjs.