This was already fixed on non-Darwin, but the fix missed that it was
also reintroduced for the Darwin code path at the same time.
Fixes: dd5d2482c9 ("emacs: Fix accidental double wrapping")
Warning about future breaking changes is wrong.
- It suggests that the maintainers don't value backwards compatibility.
They do.
- It implies that other parts of Nixpkgs won't ever break. They will.
- It implies that a well-defined "public" interface exists. It doesn't.
- If the reasons above didn't apply, it should have been in the manual
instead.
Breaking changes will come, especially to the interface. That can be the
only way we can make progress without breaking the image _contents_.
I don't think dockerTools is any different from most of Nixpkgs in
these regards.
`buildRustPackage` currently accepts `cargoSha256` as a hash for
vendored dependencies. This change adds `cargoHash` which accepts SRI
hashes, setting `outputHashAlgo` to `null`.
The hash mismatch message still uses `cargoSha256` as an example,
which it probably should until we completely switch to SRI hashes.
By default, Perl versions since 5.8.1 use randomization to make hashes
resistant to complexity attacks.
That randomization makes building VM images such as ubuntu1804x86_64
non-deterministic because the (imported) derivations built by
deb/deb-closure.pl are not stable.
This can easily be observed by repeating the following sequence of
commands and noting the path of the image's .drv:
nix-instantiate -E '(import <nixpkgs> {}).vmTools.diskImageFuns.ubuntu1804x86_64 {}'
nix-store --delete /nix/store/*ubuntu-18.04-bionic-amd64.nix
One source of non-determinism is the handling of Provides/Replaces,
which depends on the order of iteration over %packages. Here is a
diff showing the corresponding change in output:
>>> awk
-virtual awk: using original-awk
- original-awk: libc6 (>= 2.14)
+virtual awk: using mawk
+ mawk: libc6 (>= 2.14)
- mawk: libc6 (>= 2.14)
->>> libc6
This patch sorts packages by name for Provides/Replaces processing,
which seems to result in stable output.
(If the above turns out not to be sufficient, one could also set the
PERL_HASH_SEED and PERL_PERTURB_KEYS environment variables, documented
in 'perlrun', to disable Perl's built-in randomization. Complexity
attacks are not an issue as we control and trust all inputs.)
Using the full store hash as the random seed occasionally caused
reference cycles when the invocation was stored in output artifacts.
For example, cross-compiled gcc was failing due to this:
https://hydra.nixos.org/eval/1631713#tabs-now-fail
Simply truncating the hash is sufficient to avoid this.
When invoking a simple Ada program with `gcc` from `gnats10`, the
following warnings are shown:
```
$ gcc -c conftest.adb
gnat1: warning: command-line option ‘-Wformat=1’ is valid for C/C++/ObjC/ObjC++ but not for Ada
gnat1: warning: command-line option ‘-Wformat-security’ is valid for C/C++/ObjC/ObjC++ but not for Ada
gnat1: warning: ‘-Werror=’ argument ‘-Werror=format-security’ is not valid for Ada
$ echo $?
0
```
This is only spammy when compiling Ada programs inside a Nix derivation,
but certain configure scripts (such as the ./configure script from the
gcc that's built by coreboot's `make crossgcc` command) fail entirely
when getting that warning output.
https://nixos.wiki/wiki/Coreboot currently suggests manually running
> NIX_HARDENING_ENABLE="${NIX_HARDENING_ENABLE/ format/}" make crossgcc
… but actually teaching the nixpkgs-provided cc wrapper that `format`
isn't supported as a hardening flag seems to be the more canonical way
to do this in nixpgks.
After this, Ada programs still compile:
```
$ gcc -c conftest.adb
$ echo $?
0
```
And the compiler output is empty.
As @lopsided98 points out in #105305, since the hashes are now target
sensative, and until we find reason to actually care to test what they
are exactly, we are best just normalizing them away in the tests.
- Generate a link to the initramfs file with an appropriate file
extension, guessed based on the compressor by default
- Use correct metadata in u-boot images if generated, up to now this
was hardcoded to gzip and would silently generate an erroneous image
if another compressor was specified
- Document all the parameters
- Improve cross-building compatibility, by allowing passing either a
string as before, or a function taking a package set and returning the
path to a compressor in the "compressor" argument of the
function.
- Support more compression algorithms
- Place compressor executable function and arguments in passthru, for
reuse when appending initramfses
Co-Authored-By: Dominik Xaver Hörl <hoe.dom@gmx.de>
Originally this was meant to support other Windows versions than just
Windows XP, but before I actually got a chance to implement this I left
the project that I implemented this for.
The code has been broken for years now and I highly doubt anyone is
interested in resurrecting this (including me), so in order to make this
less of a maintenance burden for everybody, let's remove it.
Signed-off-by: aszlig <aszlig@nix.build>
