manual: Fix typos
Thanks @matthewbauer! Co-Authored-By: Ericson2314 <git@JohnEricson.me>
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@ -259,8 +259,8 @@
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machine-code-producing tools, we're done. And indeed
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<varname>buildInputs</varname> and <varname>nativeBuildInputs</varname>
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have covered these simpler build-time and run-time (respectively) changes
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for many years. But if the depedency does produce machine code, we might
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need to worry about it's target platform too. In principle, that target
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for many years. But if the dependency does produce machine code, we might
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need to worry about its target platform too. In principle, that target
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platform might be any of the depending package's build, host, or target
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platforms, but we prohibit dependencies from a "later" platform to an
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earlier platform to limit confusion because we've never seen a legitimate
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@ -270,7 +270,7 @@
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<para>
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Finally, if the depending package is a compiler or other
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machine-code-producing tool, it might need dependencies that run at "emit
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time". This is for compilers that (regrettably) insist on being in built
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time". This is for compilers that (regrettably) insist on being built
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together with their source langauges' standard libraries. Assuming build !=
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host != target, a run-time dependency of the standard library cannot be run
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at the compiler's build time or run time, but only at the run time of code
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@ -485,9 +485,9 @@ nix-build <nixpkgs> --arg crossSystem '{ config = "<arch>-<os>
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<xref
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linkend="ssec-cross-dependency-categorization"/> are specified as
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lists of derivations given to <varname>mkDerivation</varname>, as
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documented in <xref linkend="ssec-stdenv-dependencies"/>. In short, the
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documented in <xref linkend="ssec-stdenv-dependencies"/>. In short,
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each list of dependencies for "host → target" of "foo → bar" is called
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<varname>depsFooBar</varname>, with the exceptions for backwards
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<varname>depsFooBar</varname>, with exceptions for backwards
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compatibility that <varname>depsBuildHost</varname> is instead called
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<varname>nativeBuildInputs</varname> and <varname>depsHostTarget</varname>
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is instead called <varname>buildInputs</varname>. Nixpkgs is now structured
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@ -501,13 +501,13 @@ nix-build <nixpkgs> --arg crossSystem '{ config = "<arch>-<os>
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</para>
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<para>
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Now, for most of Nixpkgs's history, there was no
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Now, for most of Nixpkgs's history, there were no
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<varname>pkgsFooBar</varname> attributes, and most packages have not been
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refactored to use it explicitly. Prior to those, there were just
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<varname>buildPackages</varname>, <varname>pkgs</varname>, and
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<varname>targetPackages</varname>. Those are now redefined as aliases to
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<varname>pkgsBuildHost</varname>, <varname>pkgsHostTarget</varname>, and
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<varname>pkgsTargetTarget</varname>. It is fine, indeed if anything
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<varname>pkgsTargetTarget</varname>. It is acceptable, even
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recommended, to use them for libraries to show that the host platform is
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irrelevant.
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</para>
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@ -523,12 +523,12 @@ nix-build <nixpkgs> --arg crossSystem '{ config = "<arch>-<os>
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their dependencies into the multiple lists described above. And indeed,
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asking that users both sort their dependencies, <emphasis>and</emphasis>
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take them from the right attribute set, is both too onerous and redundant,
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so the recommend approach (for now) is to continue just categorizing by
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so the recommended approach (for now) is to continue just categorizing by
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list and not using an explicit package set.
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</para>
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<para>
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No make this work, we "splice" together the six
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To make this work, we "splice" together the six
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<varname>pkgsFooBar</varname> package sets and have
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<varname>callPackage</varname> actually take its arguments from that. This
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is currently implemented in <filename>pkgs/top-level/splice.nix</filename>.
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@ -550,7 +550,7 @@ nix-build <nixpkgs> --arg crossSystem '{ config = "<arch>-<os>
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<filename>pkgs/top-level/stage.nix</filename> "ties the knot" (creates the
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fixed point) of each stage. The package sets are defined per-stage however,
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so they can be thought of as edges between stages (the nodes) in a graph.
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Compositions like <literal>pkgsBuildTarget.TargetPackages</literal> can be
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Compositions like <literal>pkgsBuildTarget.targetPackages</literal> can be
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thought of as paths to this graph.
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</para>
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@ -581,12 +581,12 @@ nix-build <nixpkgs> --arg crossSystem '{ config = "<arch>-<os>
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<varname>pkgsHostTarget</varname> refers to the current one, and
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<varname>pkgsTargetTarget</varname> refers to the next one. When there is
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no previous or next stage, they instead refer to the current stage. Note
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how all the invariants about the mapping between dependency and depending
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how all the invariants regarding the mapping between dependency and depending
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packages' build host and target platforms are preserved.
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<varname>pkgsBuildTarget</varname> and <varname>pkgsHostHost</varname> are
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more complex in that the stage fitting the requirements isn't always a
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fixed chain of "prevs" and "nexts" away (modulo the "saturating"
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self-references at the ends). We just special case instead. All the primary
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self-references at the ends). We just special case each instead. All the primary
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edges are implemented is in <filename>pkgs/stdenv/booter.nix</filename>,
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and secondarily aliases in <filename>pkgs/top-level/stage.nix</filename>.
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</para>
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@ -642,10 +642,10 @@ nix-build <nixpkgs> --arg crossSystem '{ config = "<arch>-<os>
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</para>
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<para>
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Second, it is because this is a frequent source of hard-to-follow
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"infinite recursions" / cycles. When only packages sets that don't mention
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target are used, the package set forms a directly acyclic graph. This
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means that all cycles that exist are confirmed to one stage. This means
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they are a lot smaller, so easier to follow in the code or a backtrace. It
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"infinite recursions" / cycles. When only package sets that don't mention
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target are used, the package set forms a directed acyclic graph. This
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means that all cycles that exist are confined to one stage. This means
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they are a lot smaller, and easier to follow in the code or a backtrace. It
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also means they are present in native and cross builds alike, and so more
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likely to be caught by CI and other users.
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</para>
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@ -653,7 +653,7 @@ nix-build <nixpkgs> --arg crossSystem '{ config = "<arch>-<os>
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Thirdly, it is because everything target-mentioning only exists to
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accommodate compilers with lousy build systems that insist on the compiler
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itself and standard library being built together. Of course that is bad
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because bigger derivation means longer rebuilds. It is also subpar because
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because bigger derivations means longer rebuilds. It is also problematic because
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it tends to make the standard libraries less like other libraries than
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they could be, complicating code and build systems alike. Because of the
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other problems, and because of these innate disadvantages, compilers ought
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@ -224,7 +224,7 @@ genericBuild
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the dependency is needed at run-time or build-time, a concept that makes
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perfect sense outside of cross compilation. By default, the
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run-time/build-time distinction is just a hint for mental clarity, but with
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<varname>strictDeps</varname> set it is somewhat enforced even in the native
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<varname>strictDeps</varname> set it is mostly enforced even in the native
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case.
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</para>
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