Use precompiled DLLs on Windows

[ararslan]

Lets see what AppVeyor has to say about this...

[ararslan]

Doesn't like it.

(The Travis failed checks are because I canceled those builds.)

[tkelman]

probably needs os = :Windows

[ararslan]

@tkelman Ah, good idea. I'll add that. I assume that won't help this error though?:

LoadError: I don't know how to unpack C:\Users\appveyor\.julia\v0.5\ZStd\deps\downloads\:libzstd.1.0.0.dll

I assume that has something to do with the unpacked_dir argument, since a DLL doesn't really need unpacking in the sense of an archive.

[tkelman]

the colon in the filename is causing issues. did you build both 32 and 64 bit binaries in the same zip?

[tkelman]

oh yeah i don't think it can handle a raw dll properly.

[ararslan]

the colon in the filename is causing issues.

Hm. That's the URL that BinTray gave me. Are there alternative paths you can use on BinTray?

did you build both 32 and 64 bit binaries in the same zip?

Nope. Do I use the i686-w64-mingw32-gcc to compile the 32-bit DLL? I'll compile that too and stick it in a .zip.

oh yeah i don't think it can handle a raw dll properly.

:(

[tkelman]

should make a usr/bin in the zip files and put the dll there, then you shouldn't need to specify unpacked_dir

from what I remember the last time I tried setting unpacked_dir = "." or otherwise empty it didn't go well

[ararslan]

Awesome, 64-bit Windows works!! The problem now is that 32-bit still does not, and it's not exactly clear why...

LoadError: Provider BinDeps.Binaries failed to satisfy dependency zstd
while loading C:\Users\appveyor\.julia\v0.5\ZStd\deps\build.jl, in expression starting on line 31

[tkelman]

dlopen may have failed

[ararslan]

Doesn't dlopen usually tell you when it fails to open something though?

[tkelman]

not when called by bindeps, annoyingly

[ararslan]

Could something cryptic like this happen if I didn't do the cross-compiling for 32-bit Windows correctly? I used i686-w64-mingw32-gcc on OS X (64-bit).

[tkelman]

it may be missing a dependency. usually i use dependency walker to check for that when I'm on windows, not sure the best tool to use from the cross compiler system

[ararslan]

You mean Zstandard itself could be missing a dependency on 32-bit Windows?

[tkelman]

right. if I had to guess, it might need libgcc_s on 32 bit for some integer operation that wouldn't otherwise be provided in the 32 bit windows c runtime library

[tkelman]

though that should be available from julia, so maybe it's something else