| 10 Aug 2021 |
 Las | In reply to @sternenseemann:systemli.org
I think it performs much worse for big repos I tested it on Nixpkgs lol | 12:39:23 |
| Las | Though perhaps it was because I had already fetched an earlier commit? | 12:39:43 |
 niksnut | The github fetcher is way faster than git. | 12:42:25 |
| niksnut | Often it's even faster in cases where git can do an incremental fetch. | 12:43:18 |
 sterni | In reply to @pamplemouss_:matrix.org
I am trying to compile nix a non nixos (ubuntu) using clang.
I am using nix develop .#nix-clang11Stdenv (thanks to https://github.com/NixOS/nix/pull/4996) , but I get plenty of errors when linking src/libutil/libnixutil.so
/nix/store/qvc6cz5d43jhhm4a3r48xkrc82xh1s95-binutils-2.35.1/bin/ld: src/libutil/libnixutil.so.p/archive.cc.o: in function `nix::dump(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, nix::Sink&, std::function<bool (std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)>&)':
/src/nix/build/../src/libutil/archive.cc:73: undefined reference to `std::allocator<char>::allocator()'
[... and many more…]
Feels like the flake.nix might be missing stdlib, but I tried adding libcxx without success, and libstdcxx5 fails to build.
have you tried llvmPackages_11.libcxxStdenv? | 12:44:42 |
| Las | In reply to @niksnut:matrix.org
The github fetcher is way faster than git. Do you think there are any ways of making the Git fetcher faster? | 12:45:15 |
| sterni | also these usually use binutils' ld.bfd which sometimes causes weird problems linking C++, so pkgsLLVM.stdenv may be worth a try which uses lld | 12:46:35 |
| sterni | * pamplemousse: also these usually use binutils' ld.bfd which sometimes causes weird problems linking C++, so pkgsLLVM.stdenv may be worth a try which uses lld | 12:46:45 |
| niksnut | Quick test: fetching github:NixOS/nixpkgs => 16.5s, git+https://github.com/NixOS/nixpkgs => 131.5s, doing the latter again => 11.3s | 12:48:54 |
| niksnut | Fetching git+https://github.com/NixOS/nixpkgs?shallow=1 => 85.2s | 12:52:31 |
| niksnut | That's probably the best we can do with git. | 12:52:54 |
| Las | Hmm, thanks | 13:00:40 |
| Las | The issue is you can't check commit signatures when using the github fetcher | 13:01:01 |
| Las | In reply to @niksnut:matrix.org
Fetching git+https://github.com/NixOS/nixpkgs?shallow=1 => 85.2s I tried this on my own machine, and it did indeed take ages (so long I interrupted it), but time git clone git://github.com/NixOS/nixpkgs --depth 1 took 10.31 seconds according to time. | 13:31:10 |
| Las | Are you sure something isn't broken in the Git integration in Nix? This is an extreme difference. | 13:31:53 |
| niksnut | In reply to @Las:matrix.org
I tried this on my own machine, and it did indeed take ages (so long I interrupted it), but time git clone git://github.com/NixOS/nixpkgs --depth 1 took 10.31 seconds according to time. Yes, that's what ?shallow= does. | 13:32:06 |
| niksnut | hm | 13:32:18 |
| Las | I wonder why it takes so long then | 13:32:20 |
 balsoft | BTW I can confirm that Nix' fetcher is way slower than fetching manually | 13:32:38 |
| niksnut | Nix just calls git, it doesn't fetch itself | 13:33:29 |
| niksnut | Looks like we're not passing --depth 1 | 13:34:39 |
| Las | isn't it not shallow then? | 13:34:48 |
| niksnut | yeah | 13:36:14 |
 pamplemousse | In reply to @sternenseemann:systemli.org
pamplemousse: also these usually use binutils' ld.bfd which sometimes causes weird problems linking C++, so pkgsLLVM.stdenv may be worth a try which uses lld I think https://github.com/NixOS/nix/pull/4996/files#diff-206b9ce276ab5971a2489d75eb1b12999d4bf3843b7988cbe8d687cfde61dea0L600-R631 makes nix develop automatically pick the stdenv corresponding to what I need (I do nix develop .#nix-clang11Stdenv. | 16:10:34 |
| pamplemousse | sterni (he/him): and I get an /nix/store/qvc6cz5d43jhhm4a3r48xkrc82xh1s95-binutils-2.35.1/bin/ld: cannot find -lc++abi when trying to use llvmPackages_11.libcxx | 17:50:04 |
| sterni | libcxx or libcxxStdenv? | 17:50:41 |
| pamplemousse | libcxx
got an /nix/store/qvc6cz5d43jhhm4a3r48xkrc82xh1s95-binutils-2.35.1/bin/ld: cannot find -lc++ with libcxxStdenv
(both from llvmPackages_11) | 17:59:58 |
| sterni | what were you doing exactly? libcxxabi is in extraPackages of libcxxClang, so it should not fail in this way | 18:01:23 |
 Vladimír Čunát | In reply to @Las:matrix.org
The issue is you can't check commit signatures when using the github fetcher Does it make sense to check git signature unless you have the whole history? (up to that commit; in particular, no --depth stuff) | 18:49:20 |
| Las | In reply to @vcunat:matrix.org
Does it make sense to check git signature unless you have the whole history? (up to that commit; in particular, no --depth stuff) I'm not sure. I found other ways of heavily reducing the time it takes to fetch Nixpkgs, specifically --filter=tree:0, but it still takes 4 times as much time. | 18:56:55 |
