Problems compiling in Windows

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Problems compiling in Windows

Post by srochford » Sun Jun 27, 2021 6:43 pm

I'm trying to compile v31/fixes. I've got a Windows 10 machine with MingGW, Visual Studio 2019, QT and a few other bits installed and (I think!) configured properly. I've updated the vcxproj files so that they work with Visual Studio 2019.

When I run powershell .\configure.ps1 everything starts OK (compiling the stuff under mythtv\platform\win32\msvc) and then gets to the point where it compiles ffmpeg. There's a warning that it will take a while with no output and then loads of output from the compilation appears. There are multiple warnings (eg stuff like warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data) Finally, there's a linker warning, a series of errors and it fails:

LINK : warning LNK4044: unrecognized option '/lmythavutil'; ignored
Creating library libswscale/libmythswscale.lib and object libswscale/libmythswscale.exp
vscale.o : error LNK2001: unresolved external symbol av_log
libswscale\libmythswscale-5.dll : fatal error LNK1120: 18 unresolved externals
make: *** [libswscale/libmythswscale-5.dll] Error 96

I think all the errors are because the mythavutil library has not been linked - there is a file created called avutil.lib in the libavutil folder under ffmpeg. In the same folder, there's a file avutil-56.def which looks like a list of exports from that library and most of the missing "unresolved external symbols" are listed there.

I think (but I'm no expert!) that there's something wrong with the process that calls the linker but I don't know where to start looking - I can't find anything obvious in any of the Makefiles.

Any ideas??


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