stdenv, gcc: rename postPostInstall -> preFixup #223634
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This reverts commit 254426e.
The command
```
nix-build -A tests.trivial-builders.references --show-trace
```
fails eval with
```
in job ‘nixpkgs.tests.trivial-builders.references’:
error: The option `meta.description' does not exist. Definition values:
- In `makeTest parameters': "Run the Nixpkgs trivial builders tests"
```
because `meta.description` and `meta.license` are not valid for
`nixosTest`s (they are valid for `mkDerivation` of course).
This has been causing Hydra eval failures:
https://hydra.nixos.org/jobset/nixos/pr-209870-gcc-external-bootstrap#tabs-errors
Let's fix eval by removing these attributes.
The command at the top of this file fails to evaluate: ``` $ nix-build -A tests.pkg-config.defaultPkgConfigPackages in job ‘nixpkgs.tests.pkg-config.defaultPkgConfigPackages.tests-combined.x86_64-linux’: error: pkg-config module `recurseForDerivations` is not defined to be a derivation. Please check the attribute value for `recurseForDerivations` in `pkgs/top-level/pkg-config-packages.nix` in Nixpkgs. ``` This is also causing eval errors on Hydra: https://hydra.nixos.org/jobset/nixos/pr-209870-gcc-external-bootstrap#tabs-errors Let's filter out `recurseForDerivations=true` from the attrset, since it exists mainly as a flag to signal special handling when recursing.
When wrapping `clang` and using a `gccForLibs` whose `libgcc` is in
its own output (rather than the `lib` output), this commit will adds
`-L${gccForLibs.libgcc}/lib` to `cc-ldflags`.
If that flag is not added, `firefox` will fail to compile because it
invokes `clang-wrapper` with `-fuse-ld=lld` and passes `-lgcc_s` to
`lld`, but does not tell `lld` where to find `libgcc_s.so`. In that
situation, firefox will fail to link.
The Nix-driven bootstrap of gcc expects that `stdenv.cc.cc` has a `version` attribute, except if `stdenv.cc` is the `bootstrapFiles`. This commit causes `ccache-links`'s `cc-wrapper` to `inherit version` in order to satisfy that requirement. Without this commit, ofborg CI will fail. Co-authored-by: Sandro <sandro.jaeckel@gmail.com>
This commit has no effect on eval. It simply factors out a common subexpression.
This commit has no effect on eval. It simply reorganizes the `gcc11` and `gcc12` expressions so they apply a list of `overrideAttrs`. The list is currently empty.
#### Summary
By default, when you type `make`, GCC will compile itself three
times. This PR inhibits that behavior by configuring GCC with
`--disable-bootstrap`, and reimplements the triple-rebuild using
Nix rather than `make`/`sh`.
#### Immediate Benefits
- Allow `gcc11` and `gcc12` on `aarch64` (without needing new
`bootstrapFiles`)
- Faster stdenv rebuilds: the third compilation of gcc
(i.e. stageCompare) is no longer a `drvInput` of the final stdenv.
This allows Nix to build stageCompare in parallel with the rest of
nixpkgs instead of in series.
- No more copying `libgcc_s` out of the bootstrap-files or other
derivations
- No more Frankenstein compiler: the final gcc and the libraries it
links against (mpfr, mpc, isl, glibc) are all built by the same
compiler (xgcc) instead of a mixture of the bootstrapFiles'
compiler and xgcc.
- No more [static lib{mpfr,mpc,gmp,isl}.a hack]
- Many other small `stdenv` hacks eliminated
- `gcc` and `clang` share the same codepath for more of `cc-wrapper`.
#### Future Benefits
- This should allow using a [foreign] `bootstrap-files` so long as
`hostPlatform.canExecute bootstrapFiles`.
- This should allow each of the libraries that ship with `gcc`
(lib{backtrace, atomic, cc1, decnumber, ffi, gomp, iberty,
offloadatomic, quadmath, sanitizer, ssp, stdc++-v3, vtv}) to be
built in separate (one-liner) derivations which `inherit src;`
from `gcc`, much like #132343
#### Incorporates
- #210004
- #36948 (unreverted)
- #210325
- #210118
- #210132
- #210109
- #213909
- #216136
- #216237
- #210019
- #216232
- #216016
- #217977
- #217995
#### Closes
- Closes #108305
- Closes #108111
- Closes #201254
- Closes #208412
#### Credits
This project was made possible by three important insights, none of
which were mine:
1. @Ericson2314 was the first to advocate for this change, and
probably the first to appreciate its advantages. Nix-driven
(external) bootstrap is "cross by default".
2. @trofi has figured out a lot about how to get gcc to not mix up
the copy of `libstdc++` that it depends on with the copy that it
builds, by moving the `bootstrapFiles`' `libstdc++` into a
[versioned directory]. This allows a Nix-driven bootstrap of gcc
without the final gcc would still having references to the
`bootstrapFiles`.
3. Using the undocumented variable [`user-defined-trusted-dirs`]
when building glibc. When glibc `dlopen()`s `libgcc_s.so`, it
uses a completely different and totally special set of rules for
finding `libgcc_s.so`. This trick is the only way we can put
`libgcc_s.so` in its own separate outpath without creating
circular dependencies or dependencies on the bootstrapFiles. I
would never have guessed to use this (or that it existed!) if it
were not for a [comment in guix] which @Mic92 [mentioned].
My own role in this PR was basically: being available to go on a
coding binge at an opportune moment, so we wouldn't waste a
[crisis].
[aarch64-compare-ofborg]: https://github.com/NixOS/nixpkgs/pull/209870/checks?check_run_id=10662822938
[amd64-compare-ofborg]: https://github.com/NixOS/nixpkgs/pull/209870/checks?check_run_id=10662825857
[nonexistent sysroot]: #210004
[versioned directory]: #209054
[`user-defined-trusted-dirs`]: https://sourceware.org/legacy-ml/libc-help/2013-11/msg00026.html
[comment in guix]: https://github.com/guix-mirror/guix/blob/5e4ec8218142eee8e6e148e787381a5ef891c5b1/gnu/packages/gcc.scm#L253
[mentioned]: #210112 (comment)
[crisis]: #108305
[foreign]: #170857 (comment)
[static lib{mpfr,mpc,gmp,isl}.a hack]: https://github.com/NixOS/nixpkgs/blob/2f1948af9c984ebb82dfd618e67dc949755823e2/pkgs/stdenv/linux/default.nix#L380
This commit adds `gcc/common/checksum.nix`, which contains code common to both gcc11 and gcc12, implementing the `enableChecksum` feature. When gcc's built-in bootstrap (`--enable-bootstrap`) is used, gcc compiles itself three times and compares a hash of the unlinked `.o` files from the second and third compilation. The `enableChecksum=true` parameter performs the same comparison as part of the `postInstall` phase. Notably, `enableChecksum=true` can be used with `enableBootstrap=false`. Co-authored-by: Sandro <sandro.jaeckel@gmail.com>
This commit adds a derivation `gcc-stageCompare` to `pkgs/test/stdenv/default.nix`. It is important to always build this derivation whenever building `stdenv`! Because we are using a Nix-driven bootstrap instead of gcc's built-in `--enable-bootstrap`, the `gcc` derivation no longer performs the post-self-compilation sanity check. You must build this derivation in order to perform that sanity check. The major benefit of this new approach is that the sanity check (which involves a third compilation of gcc) can be performed *concurrently* with all packages that depend on `stdenv`, rather than serially. Since `stdenv` has very little derivation-level parallelism it cannot take advantage of more than one or perhaps two builders. If you have three or more builders this commit will reduce the time-to-rebuild-stdenv by around 20% (one of three gcc rebuilds is removed from the critical path, and stdenv's build time is dominated by roughly 3*gcc + 1*binutils + 1*bison-test-suite). Co-authored-by: Sandro <sandro.jaeckel@gmail.com>
The Nix-driven bootstrap of gcc resulted in some changes to the structure of the `libgccjit` outpaths, and also added an additional output (`libgcc`) to `gcc`. This commit makes the corresponding changes in the `emacs` derivation in order to not break emacs. Emacs is the only user of `libgccjit` in nixpkgs at the moment.
This commit implements @SuperSandro2000's suggestion here: #209870 (review) I am submitting it as a separate PR in order to avoid a full rebuild on Hydra.
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Description of changes
This commit implements @SuperSandro2000's suggestion here:
#209870 (review)
I am submitting it as a separate PR in order to avoid a full rebuild on Hydra.
Things done
sandbox = trueset innix.conf? (See Nix manual)nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage./result/bin/)