fix(nix): build kcov in the dev shell on macOS#9681
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`zig build build-ci` builds the custom kcov coverage tool from source on every platform, but the dev shell only provided kcov's link dependencies on Linux, so on macOS the build failed with "unable to find dynamic system library 'z'/'curl'". Provide curl/zlib/pkg-config on all platforms, and on macOS add libdwarf (kcov links it as "dwarf"). kcov resolves system libraries through pkg-config but asks for the module names "z"/"dwarf", which nixpkgs ships as "zlib"/"libdwarf"; add alias .pc files so those resolve (the nix pkg-config wrapper only reads .pc dirs from buildInputs, not an exported PKG_CONFIG_PATH). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Problem
zig build build-ci(theminiciflow) builds the custom kcov coverage tool from source on every platform, but the dev shell only provided kcov's link dependencies on Linux (++ optionals isLinux kcovBuildDeps). On macOS the build failed:Root cause
kcov links its system libraries via zig's
linkSystemLibrary, which resolves them through pkg-config. nixpkgs ships these as the moduleszlib/libcurl/libdwarf, but kcov asks forz/curl/dwarf.curlhappens to resolve;zanddwarfdo not. The nix pkg-config wrapper only reads.pcdirectories frombuildInputs(viaPKG_CONFIG_PATH_FOR_TARGET), not an exportedPKG_CONFIG_PATH, so the aliases must be real packages.Fix (
src/flake.nix)pkg-config/curl/zlibon all platforms (not just Linux)..pcpackages sopkg-config z→ zlib andpkg-config dwarf→ libdwarf resolve.libdwarf(kcov links it asdwarf); keepelfutilsLinux-only (kcov uses libdw/libelf there).Verification (macOS, inside
nix develop ./src)pkg-config zandpkg-config dwarfboth resolvezig build build-coverage-tools→ exit 0zig build build-ci --summary all --color off→ exit 0, no failures (kcov compiles + installs)🤖 Generated with Claude Code