如何诊断失败的 nix-build？

Question

如何诊断 nix-build 失败？

目前我看到输出为：

nix build -v
warning: dumping very large path (> 256 MiB); this may run out of memory
building '/nix/store/fdrm6kbm68vld3bhfjizv684ck725lyf-blog.drv'...
builder for '/nix/store/fdrm6kbm68vld3bhfjizv684ck725lyf-blog.drv' failed with exit code 1; last 5 log lines:
  unpacking sources
  unpacking source archive /nix/store/s7r5vlvp49ad6a9d5hqhsiaxw691iyhf-Blog
  source root is Blog
  patching sources
  configuring
[0 built (1 failed), 0.0 MiB DL]
error: build of '/nix/store/fdrm6kbm68vld3bhfjizv684ck725lyf-blog.drv' failed

我希望找到一些日志/错误，说明为什么它无法构建？

---

以下来自/sf/answers/3308506281/：

我已经尝试添加build-cache-failures = true;到，default.nix但是我仍然看不到以下输出：

nix-store --read-log

而nix-store --query-failed-paths结果：

error: no operation specified
Try 'nix-store --help' for more information.

Answer 1

也可以看看：

• 在 nixpkgs 文档中的nix-shell 中构建 stdenv 包
• Nix-build-phases：在 nixos 讨论中以交互方式运行 nix 构建阶段
• nixos wiki 中使用 nix-shell 的开发环境
• nixpkgs 中的 runPhase 函数
  • eval "${!curPhase:-$curPhase}"
  • cd "${sourceRoot:-.}"
• nixpkgs 中的 genericBuild 函数- 调用runPhase $curPhase

调试包的构建过程：

代替nix-build

nix-build -E 'with import <nixpkgs> {}; callPackage ./. {}'

运行nix-shell进入构建环境

nix-shell -E 'with import <nixpkgs> {}; callPackage ./. {}'

然后运行构建阶段

# run build in tempdir
cd $(mktemp -d)

# dont install to /nix/store
for n in $outputs; do eval export $n=$PWD/result-$n; done

# https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh
phases="${prePhases[*]:-} unpackPhase patchPhase ${preConfigurePhases[*]:-} \
    configurePhase ${preBuildPhases[*]:-} buildPhase checkPhase \
    ${preInstallPhases[*]:-} installPhase ${preFixupPhases[*]:-} fixupPhase installCheckPhase \
    ${preDistPhases[*]:-} distPhase ${postPhases[*]:-}";

echo writing nix-build-phases.txt
for curPhase in $phases; do
    echo "eval \"\${$curPhase:-$curPhase}\""
    if [ "$curPhase" = unpackPhase ]; then
        echo '[ -n "${sourceRoot:-}" ] && chmod +x "${sourceRoot}"'
        echo 'cd "${sourceRoot:-.}"'
    fi
done >nix-build-phases.txt

echo "please manually run the build phases in nix-build-phases.txt"
echo
cat nix-build-phases.txt

示例 nix-build-phases.txt

eval "${unpackPhase:-unpackPhase}"
[ -n "${sourceRoot:-}" ] && chmod +x "${sourceRoot}"
cd "${sourceRoot:-.}"
eval "${patchPhase:-patchPhase}"
eval "${updateAutotoolsGnuConfigScriptsPhase:-updateAutotoolsGnuConfigScriptsPhase}"
eval "${configurePhase:-configurePhase}"
eval "${buildPhase:-buildPhase}"
eval "${checkPhase:-checkPhase}"
eval "${installPhase:-installPhase}"
eval "${fixupPhase:-fixupPhase}"
eval "${installCheckPhase:-installCheckPhase}"
eval "${distPhase:-distPhase}"

在此构建环境中，您可以

• 找出构建错误的原因（哪个构建阶段失败了？）
• 修改构建命令，例如重新定义buildPhase：运行type buildPhase打印旧阶段、复制旧阶段、修改阶段、粘贴新阶段
• 运行修改后的构建命令。这可能比完全重建更快

注意：构建者可以执行不同的构建阶段。实际的构建阶段存储在变量中，例如prePhases或preConfigurePhases

问题：构建脚本运行，set -e因此它将在出现第一个错误时退出，但这会退出交互式 shell。这是 bash shell 的限制，因此理想情况下，我们将在 bash 调试器中运行构建脚本，在出现第一个错误时停止执行，修改命令，后退并重复执行命令，并允许检查状态。

eval "${unpackPhase:-unpackPhase}"
[ -n "${sourceRoot:-}" ] && chmod +x "${sourceRoot}"
cd "${sourceRoot:-.}"
eval "${patchPhase:-patchPhase}"
eval "${updateAutotoolsGnuConfigScriptsPhase:-updateAutotoolsGnuConfigScriptsPhase}"
eval "${configurePhase:-configurePhase}"
eval "${buildPhase:-buildPhase}"
eval "${checkPhase:-checkPhase}"
eval "${installPhase:-installPhase}"
eval "${fixupPhase:-fixupPhase}"
eval "${installCheckPhase:-installCheckPhase}"
eval "${distPhase:-distPhase}"

Answer 2

阅读日志应该有效。你有具体说明推导过程吗？ nix-store --read-log /nix/store/fdrm6kbm68vld3bhfjizv684ck725lyf-blog.drv