Issue linking with arm64 and musl (Alpine 3.18)

[Fishrock123]

Building git2 causes an issue when build for Alpine linux 3.18 targeting arm64.

See this rustc issue: rust-lang/rustup#3324 (comment) - I am not sure if this is a rust compiler issue of an issue with e.g. libgit2-sys, but it seems more likely that it is a crate issue.

Here is my linking error:

10.06 error: linking with `cc` failed: exit status: 1
10.06   |
10.06   = note: LC_ALL="C" PATH="/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/bin:/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/bin/self-contained:/usr/local/cargo/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" VSLANG="1033" "cc" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/self-contained/crt1.o" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/self-contained/crti.o" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/self-contained/crtbegin.o" "/tmp/rustckg2trO/symbols.o" "/app/target/release/build/app-c0f4da874ae9cb79/build_script_build-c0f4da874ae9cb79.build_script_build.f21e8405a8680897-cgu.0.rcgu.o" "/app/target/release/build/app-c0f4da874ae9cb79/build_script_build-c0f4da874ae9cb79.5cs5zj006xi1kszr.rcgu.o" "-Wl,--as-needed" "-L" "/app/target/release/deps" "-L" "/app/target/release/build/libgit2-sys-b0265079e065ab06/out/build" "-L" "/app/target/release/build/libz-sys-c1e8829c1e9ea85f/out/lib" "-L" "/app/target/release/build/libz-sys-c1e8829c1e9ea85f/out/lib" "-L" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib" "-Wl,-Bstatic" "/app/target/release/deps/libbuilt-56c7d404c1513de9.rlib" "/app/target/release/deps/libgit2-6aa19713b6e193c1.rlib" "/app/target/release/deps/liburl-d29a55eea5f8985c.rlib" "/app/target/release/deps/libidna-1a73440288804038.rlib" "/app/target/release/deps/libunicode_normalization-76de1d961712a825.rlib" "/app/target/release/deps/libtinyvec-8d1e5b502fc4efc2.rlib" "/app/target/release/deps/libtinyvec_macros-069cbc3946ed02a8.rlib" "/app/target/release/deps/libunicode_bidi-cbc8e81f0702ea81.rlib" "/app/target/release/deps/libform_urlencoded-b5a5f80a2b2e2879.rlib" "/app/target/release/deps/libpercent_encoding-384b022fd3437573.rlib" "/app/target/release/deps/liblog-bbb4dc17ab6210af.rlib" "/app/target/release/deps/liblibgit2_sys-fedb06ffe4a81e54.rlib" "/app/target/release/deps/liblibz_sys-76293d2a5acbce7c.rlib" "/app/target/release/deps/liblibc-53797761d2e0bf05.rlib" "/app/target/release/deps/libbitflags-584c92aede70dcf2.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libstd-b13ff878e5d4772e.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libpanic_unwind-56ff67a6f2bbe26c.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libobject-b979ae03b63d8d68.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libmemchr-58cbe68a8bb2fe91.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libaddr2line-9e9fe0f60e5b4d08.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libgimli-d1dc1577e31bf044.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/librustc_demangle-121899391fa58bd9.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libstd_detect-e3f812d8bd3e0e87.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libhashbrown-8a773f116c633544.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/librustc_std_workspace_alloc-78fb926ae22d35c0.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libminiz_oxide-f64c502d42d93a67.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libadler-6e8fdf50da1f9c1f.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libunwind-594b86bee800abf8.rlib" "-lunwind" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libcfg_if-f3811e9672bf18c2.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/liblibc-30a29c0493545a48.rlib" "-lc" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/liballoc-9c89ef503a72291b.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/librustc_std_workspace_core-4c4d965152b65e95.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libcore-2b1e2f8589f4384b.rlib" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libcompiler_builtins-330cf3f82d35bd41.rlib" "-Wl,-Bdynamic" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-nostartfiles" "-L" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib" "-L" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/self-contained" "-o" "/app/target/release/build/app-c0f4da874ae9cb79/build_script_build-c0f4da874ae9cb79" "-Wl,--gc-sections" "-static" "-no-pie" "-Wl,-z,relro,-z,now" "-nodefaultlibs" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/self-contained/crtend.o" "/usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/self-contained/crtn.o"
10.06   = note: /usr/lib/gcc/aarch64-alpine-linux-musl/12.2.1/../../../../aarch64-alpine-linux-musl/bin/ld: /usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libcompiler_builtins-330cf3f82d35bd41.rlib(45c91108d938afe8-cpu_model.o): in function `init_have_lse_atomics':
10.06           /cargo/registry/src/index.crates.io-6f17d22bba15001f/compiler_builtins-0.1.103/./lib/builtins/cpu_model.c:1075: undefined reference to `getauxval'
10.06           /usr/lib/gcc/aarch64-alpine-linux-musl/12.2.1/../../../../aarch64-alpine-linux-musl/bin/ld: /usr/local/rustup/toolchains/1.74.1-aarch64-unknown-linux-musl/lib/rustlib/aarch64-unknown-linux-musl/lib/libcompiler_builtins-330cf3f82d35bd41.rlib(45c91108d938afe8-cpu_model.o): in function `init_cpu_features':
10.06           /cargo/registry/src/index.crates.io-6f17d22bba15001f/compiler_builtins-0.1.103/./lib/builtins/cpu_model.c:1373: undefined reference to `getauxval'
10.06           /usr/lib/gcc/aarch64-alpine-linux-musl/12.2.1/../../../../aarch64-alpine-linux-musl/bin/ld: /cargo/registry/src/index.crates.io-6f17d22bba15001f/compiler_builtins-0.1.103/./lib/builtins/cpu_model.c:1374: undefined reference to `getauxval'
10.06           collect2: error: ld returned 1 exit status

[ehuss]

Thanks for the report! I'm going to close as a duplicate of #706 and rust-lang/rust#89626. Unfortunately I don't think there is anything this library can do to fix the issue. rust-lang/rust#89626 contains some workarounds.