Nix on Cygwin doesn't work because DBD::SQLite doesn't work

[edolstra]

$ perl -e 'use DBD::SQLite;'
Can't load '/nix/store/nxy9c2s5443al8g601fjlg62idbzqh0w-perl-DBD-SQLite-1.35/lib/perl5/site_perl/5.10/i686-cygwin/auto/DBD/SQLite/SQLite.dll' for module DBD::SQLite: No such process at /usr/lib/perl5/5.10/i686-cygwin/DynaLoader.pm line 200.
 at -e line 1
Compilation failed in require at -e line 1.
BEGIN failed--compilation aborted at -e line 1.

The "No such process" error may be related to the base address of the DLL, but changing it using the "--image-base=..." linker flag didn't help. Running "rebaseall" didn't help either (but then it doesn't look in the Nix store so that's not surprising).

[viric]

Does this problem happen only when building nix using nix?

I'm trying to build nix master on cygwin (not using nix), and I fail even to install DBD::SQLite. Somehow it wants to call 'gcc-4' instead of 'gcc'.

[viric]

I just had to add gcc 4.x into cygwin, and install DBD::SQLite. Then I built the nix 1.0 tarball, with CC=gcc-4 CXX=g++-4, and then nix runs fine.

I haven't tried without setting gcc/g++ to 4.x for nix.
Now I'm trying to build nixpkgs' nix with that nix, having changed the native gcc-wrapper to point to gcc-4 and g++-4.

[viric]

OTH, if nix uses shared libraries, trying to run nix inside nix (maybe in the make check stage) can fail hard, if nix shared libraries of different versions don't have different names.

Windows can't load multiple DLLs with the same name - systemwide constraint (unless using winsxs). If nix shared libraries have the same name regardless of the version, the nix under 'make check' would be dynamically linked with the nix DLLs doing the build, because they were loaded first there.

[viric]

After building nix with nix and gcc-4, having disabled the doInstallCheck, I get this:

Can't exec "/nix/store/zh79050vfkrjax8kklydr559ydh3rwbg-nix-1.0/bin/nix-instantiate": Bad address at /nix/store/zh79050vfkrjax8kklydr559ydh3rwbg-nix-1.0/bin/nix-build line 166.

[viric]

I tried rebaseall with a list of all exe and dlls in the nix store (-T list), and that did not help. I had to make the dll writeable, for it to success. As for the exe, it said the exe were not 'rebaseable'; maybe here is the trouble.

[viric]

Finally I removed the perl DBD lines in configure.ac. I rebuilt all, installed (I disabled the manual generation the hard way, which also failed), and all went fine.
Now, nix-build, nix-env and nix-store work if called with "NIX_SUBSTITUTERS=".

So if the DBD stuff could be made optional (like the default substituters), it would make all easier by now.

[domenkozar]

From #nixos:

3:31:28         niksnut | ah yes, the real issue is cygwin's requirement that all DLLs have a unique load address, or something like that                                                                                    │ mattw        
13:31:38         niksnut | which is basically unsupportable in a purely functional model                                                                                                                                      │ maxipin_     
13:31:56         niksnut | cygwin has a tool called "rebaseall" that rewrites all DLLs in the system to meet this requirement   

[ghost]

nix builds on cygwin-nt 6.1 2.2.0 (0.289/5/3) x86_64
i roughly followed https://nixos.org/wiki/Nix_on_Windows which gives an idea but most of the dependencies i had to install manually via cygwin gui
after building nix, i can install hello, for example
many packages don't work, but that is a problem with nixpkgs, not nix

[chaoflow]

This issue is outdated and should be closed.

@tohl thx for reporting

[chaoflow]

For completeness: we describe a cygport file to install nix on cygwin: http://ternaris.com/lab/nix-on-windows.html#package-build-and-install-nix

[ghost]

actually the version that builds under cygwin is nix-1.8

the latest nix from unstable (nix-1.10) doesn't build because of a compilation error
undefined ENOENT in nix-collect-garbage.cc
adding #include <errno.h> might fix this issue

[ryantrinkle]

My company, Obsidian Systems would be interested in helping to support development of a Windows distribution of Nix. If anyone is interested in working on this or helping support it, please send me an email at ryan@obsidian.systems.

[vcunat]

@ryantrinkle: this particular issue will preferably be addressed by #341, IMHO.

[domenkozar]

@ryantrinkle "Windows distribution of Nix" meaning natively without cygwin?

[domenkozar]

As stated by @chaoflow this is outdated and we're very close to being perl free.