Unable to link to native library

[Michael-F-Bryan]

I'm wanting to test the examples in the README for a crate wrapping the libsignal-protocol-c library. My *-sys crate is able to link to the C library just fine (tests run on my linux laptop, Travis CI, and a contributor's computer), but when running the skeptic test the generated code isn't able to link to the signal-protocol-c library.

Does the skeptic crate do anything special when resolving dependencies that may affect linking?

Loads of compiler output

$ cargo test -v --test skeptic
       Fresh cc v1.0.37
       Fresh autocfg v0.1.2
       Fresh unicode-xid v0.1.0
       Fresh version_check v0.1.5
       Fresh semver-parser v0.7.0
       Fresh cfg-if v0.1.9
       Fresh rustc-demangle v0.1.14
       Fresh rand_core v0.4.0
       Fresh itoa v0.4.4
       Fresh same-file v1.0.4
       Fresh remove_dir_all v0.5.1
       Fresh bitflags v1.0.4
       Fresh byte-tools v0.3.1
       Fresh bytecount v0.4.0
       Fresh glob v0.2.11
       Fresh scopeguard v1.0.0
       Fresh smallvec v0.6.9
       Fresh subtle v1.0.0
       Fresh opaque-debug v0.2.2
       Fresh fake-simd v0.1.2
       Fresh cmake v0.1.40
       Fresh rand_core v0.3.1
       Fresh rand_jitter v0.1.4
       Fresh walkdir v2.2.7
       Fresh block-padding v0.1.4
       Fresh lock_api v0.2.0
       Fresh proc-macro2 v0.4.30
       Fresh libc v0.2.55
       Fresh serde v1.0.91
       Fresh ryu v0.2.8
       Fresh rand_isaac v0.1.1
       Fresh rand_hc v0.1.0
       Fresh pulldown-cmark v0.2.0
       Fresh typenum v1.10.0
       Fresh rand_xorshift v0.1.1
       Fresh byteorder v1.3.1
       Fresh quote v0.6.12
       Fresh backtrace-sys v0.1.28
       Fresh semver v0.9.0
       Fresh serde_json v1.0.39
       Fresh rand v0.4.6
       Fresh rand_os v0.1.3
       Fresh rand_pcg v0.1.2
       Fresh rand_chacha v0.1.1
       Fresh generic-array v0.12.0
       Fresh backtrace v0.3.20
       Fresh syn v0.15.34
       Fresh rustc_version v0.2.3
       Fresh tempdir v0.3.7
       Fresh serde_derive v1.0.91
       Fresh error-chain v0.12.1
       Fresh rand v0.6.5
       Fresh synstructure v0.10.2
       Fresh digest v0.8.0
       Fresh block-buffer v0.7.3
       Fresh crypto-mac v0.7.0
       Fresh libsignal-protocol-sys v0.1.0 (/home/michael/Documents/libsignal-protocol-rs/libsignal-protocol-sys)
       Fresh cargo_metadata v0.6.4
       Fresh failure_derive v0.1.5
       Fresh sha2 v0.8.0
       Fresh skeptic v0.13.4
       Fresh parking_lot_core v0.5.0
       Fresh failure v0.1.5
       Fresh hmac v0.7.0
       Fresh parking_lot v0.8.0
       Fresh libsignal-protocol v0.1.0 (/home/michael/Documents/libsignal-protocol-rs/libsignal-protocol)
    Finished dev [unoptimized + debuginfo] target(s) in 0.05s
     Running `/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/skeptic-b9dc458cacd2755b`

running 3 tests
error: linking with `cc` failed: exit code: 1
  |
  = note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-m64" "-L" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.test.7rcbfp3g-cgu.0.rcgu.o" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.test.7rcbfp3g-cgu.1.rcgu.o" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.test.7rcbfp3g-cgu.2.rcgu.o" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.test.7rcbfp3g-cgu.3.rcgu.o" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.test.7rcbfp3g-cgu.4.rcgu.o" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.test.7rcbfp3g-cgu.5.rcgu.o" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.test.7rcbfp3g-cgu.6.rcgu.o" "-o" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.exe" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.5fi6c8ty3hqyycqf.rcgu.o" "-Wl,--gc-sections" "-pie" "-Wl,-zrelro" "-Wl,-znow" "-nodefaultlibs" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps" "-L" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol-44ab010664573201.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsha2-17612fee1e57d958.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libopaque_debug-876a8bcf2102a5e7.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfake_simd-ccce268e5e38c680.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libblock_buffer-a9fd3c4395701740.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libblock_padding-ecb19f2533621600.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbyte_tools-e78f467ec2498f31.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbyteorder-bf894d96a8548d9b.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libhmac-45aeceedb4b07843.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libcrypto_mac-478f309b971040c8.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsubtle-f186a589d48a0287.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libdigest-03b5ada9621926df.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libgeneric_array-f93a150f8804f907.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libtypenum-2c5d81d6cfaf07d4.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libparking_lot-2ce8a446555fc620.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libparking_lot_core-5ea38034d97ffc93.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsmallvec-690dd5fc8f2c92ca.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand-11a629c517e0d615.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_xorshift-65c87e0e10ab25b5.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_pcg-af619038dcec4699.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_hc-d69f85a2988f33dc.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_chacha-a77b23cbd94bc5b5.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_isaac-dabbd108bee1e473.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_core-dc688c99d41bb586.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_os-220b34a332fd7b5d.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_jitter-3e853663f4890f79.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_core-11f08689a871bfc3.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblock_api-11780acf3615fb0b.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libscopeguard-45e5f1d2b9ea7b17.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol_sys-e6a37ece1ca80418.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfailure-863559f980b9bcdf.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbacktrace-671721c73f9e5925.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbacktrace_sys-6c1d55739cd05ac9.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librustc_demangle-980a98425d19cc83.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libcfg_if-c3dc09a6344ae356.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibc-e6d32eb455837b67.rlib" "-Wl,--start-group" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-30a1e0097bd1d6c9.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libpanic_unwind-2e1e5de968c56155.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libbacktrace_sys-5910362bd47bb64c.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_demangle-b3a6a1dd00522c66.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libhashbrown-b801a9001ec55852.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_alloc-512c0167b6e55e2a.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-fdbf12ec13c11586.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-f368208d2de685cd.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-c78166321a2b13a3.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-de8cd0561ba453d1.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-b77a4d50896ced4d.rlib" "-Wl,--end-group" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-c2f76c4d0d77f31b.rlib" "-Wl,-Bdynamic" "-lsignal-protocol-c" "-lutil" "-lutil" "-ldl" "-lrt" "-lpthread" "-lgcc_s" "-lc" "-lm" "-lrt" "-lpthread" "-lutil" "-lutil"
  = note: /usr/bin/ld: cannot find -lsignal-protocol-c
          collect2: error: ld returned 1 exit status
          

error: aborting due to previous error

test readme_sect_examples_line_48 ... FAILED
error: linking with `cc` failed: exit code: 1
  |
  = note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-m64" "-L" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "/tmp/rust-skeptic.ajVOEidneULS/out.test.7rcbfp3g-cgu.0.rcgu.o" "/tmp/rust-skeptic.ajVOEidneULS/out.test.7rcbfp3g-cgu.1.rcgu.o" "/tmp/rust-skeptic.ajVOEidneULS/out.test.7rcbfp3g-cgu.2.rcgu.o" "/tmp/rust-skeptic.ajVOEidneULS/out.test.7rcbfp3g-cgu.3.rcgu.o" "/tmp/rust-skeptic.ajVOEidneULS/out.test.7rcbfp3g-cgu.4.rcgu.o" "/tmp/rust-skeptic.ajVOEidneULS/out.test.7rcbfp3g-cgu.5.rcgu.o" "/tmp/rust-skeptic.ajVOEidneULS/out.test.7rcbfp3g-cgu.6.rcgu.o" "/tmp/rust-skeptic.ajVOEidneULS/out.test.7rcbfp3g-cgu.7.rcgu.o" "-o" "/tmp/rust-skeptic.ajVOEidneULS/out.exe" "/tmp/rust-skeptic.ajVOEidneULS/out.5fi6c8ty3hqyycqf.rcgu.o" "-Wl,--gc-sections" "-pie" "-Wl,-zrelro" "-Wl,-znow" "-nodefaultlibs" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps" "-L" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol-44ab010664573201.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsha2-17612fee1e57d958.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libopaque_debug-876a8bcf2102a5e7.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfake_simd-ccce268e5e38c680.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libblock_buffer-a9fd3c4395701740.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libblock_padding-ecb19f2533621600.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbyte_tools-e78f467ec2498f31.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbyteorder-bf894d96a8548d9b.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libhmac-45aeceedb4b07843.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libcrypto_mac-478f309b971040c8.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsubtle-f186a589d48a0287.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libdigest-03b5ada9621926df.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libgeneric_array-f93a150f8804f907.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libtypenum-2c5d81d6cfaf07d4.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libparking_lot-2ce8a446555fc620.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libparking_lot_core-5ea38034d97ffc93.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsmallvec-690dd5fc8f2c92ca.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand-11a629c517e0d615.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_xorshift-65c87e0e10ab25b5.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_pcg-af619038dcec4699.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_hc-d69f85a2988f33dc.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_chacha-a77b23cbd94bc5b5.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_isaac-dabbd108bee1e473.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_core-dc688c99d41bb586.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_os-220b34a332fd7b5d.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_jitter-3e853663f4890f79.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_core-11f08689a871bfc3.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblock_api-11780acf3615fb0b.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libscopeguard-45e5f1d2b9ea7b17.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol_sys-e6a37ece1ca80418.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfailure-863559f980b9bcdf.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbacktrace-671721c73f9e5925.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbacktrace_sys-6c1d55739cd05ac9.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librustc_demangle-980a98425d19cc83.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libcfg_if-c3dc09a6344ae356.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibc-e6d32eb455837b67.rlib" "-Wl,--start-group" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-30a1e0097bd1d6c9.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libpanic_unwind-2e1e5de968c56155.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libbacktrace_sys-5910362bd47bb64c.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_demangle-b3a6a1dd00522c66.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libhashbrown-b801a9001ec55852.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_alloc-512c0167b6e55e2a.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-fdbf12ec13c11586.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-f368208d2de685cd.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-c78166321a2b13a3.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-de8cd0561ba453d1.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-b77a4d50896ced4d.rlib" "-Wl,--end-group" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-c2f76c4d0d77f31b.rlib" "-Wl,-Bdynamic" "-lsignal-protocol-c" "-lutil" "-lutil" "-ldl" "-lrt" "-lpthread" "-lgcc_s" "-lc" "-lm" "-lrt" "-lpthread" "-lutil" "-lutil"
  = note: /usr/bin/ld: cannot find -lsignal-protocol-c
          collect2: error: ld returned 1 exit status
          

error: aborting due to previous error

test readme_sect_examples_line_17 ... FAILED
error: linking with `cc` failed: exit code: 1
  |
  = note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-m64" "-L" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.0.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.1.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.10.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.11.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.12.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.13.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.14.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.15.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.2.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.3.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.4.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.5.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.6.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.7.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.8.rcgu.o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.test.7rcbfp3g-cgu.9.rcgu.o" "-o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.exe" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.5fi6c8ty3hqyycqf.rcgu.o" "-Wl,--gc-sections" "-pie" "-Wl,-zrelro" "-Wl,-znow" "-nodefaultlibs" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps" "-L" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol-44ab010664573201.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsha2-17612fee1e57d958.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libopaque_debug-876a8bcf2102a5e7.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfake_simd-ccce268e5e38c680.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libblock_buffer-a9fd3c4395701740.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libblock_padding-ecb19f2533621600.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbyte_tools-e78f467ec2498f31.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbyteorder-bf894d96a8548d9b.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libhmac-45aeceedb4b07843.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libcrypto_mac-478f309b971040c8.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsubtle-f186a589d48a0287.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libdigest-03b5ada9621926df.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libgeneric_array-f93a150f8804f907.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libtypenum-2c5d81d6cfaf07d4.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libparking_lot-2ce8a446555fc620.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libparking_lot_core-5ea38034d97ffc93.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsmallvec-690dd5fc8f2c92ca.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand-11a629c517e0d615.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_xorshift-65c87e0e10ab25b5.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_pcg-af619038dcec4699.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_hc-d69f85a2988f33dc.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_chacha-a77b23cbd94bc5b5.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_isaac-dabbd108bee1e473.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_core-dc688c99d41bb586.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_os-220b34a332fd7b5d.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_jitter-3e853663f4890f79.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand_core-11f08689a871bfc3.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblock_api-11780acf3615fb0b.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libscopeguard-45e5f1d2b9ea7b17.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol_sys-e6a37ece1ca80418.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfailure-863559f980b9bcdf.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbacktrace-671721c73f9e5925.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libbacktrace_sys-6c1d55739cd05ac9.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librustc_demangle-980a98425d19cc83.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libcfg_if-c3dc09a6344ae356.rlib" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibc-e6d32eb455837b67.rlib" "-Wl,--start-group" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-30a1e0097bd1d6c9.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libpanic_unwind-2e1e5de968c56155.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libbacktrace_sys-5910362bd47bb64c.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_demangle-b3a6a1dd00522c66.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libhashbrown-b801a9001ec55852.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_alloc-512c0167b6e55e2a.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-fdbf12ec13c11586.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-f368208d2de685cd.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-c78166321a2b13a3.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-de8cd0561ba453d1.rlib" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-b77a4d50896ced4d.rlib" "-Wl,--end-group" "/home/michael/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-c2f76c4d0d77f31b.rlib" "-Wl,-Bdynamic" "-lsignal-protocol-c" "-lutil" "-lutil" "-ldl" "-lrt" "-lpthread" "-lgcc_s" "-lc" "-lm" "-lrt" "-lpthread" "-lutil" "-lutil"
  = note: /usr/bin/ld: cannot find -lsignal-protocol-c
          collect2: error: ld returned 1 exit status
          

error: aborting due to previous error

test readme_sect_examples_line_27 ... FAILED

failures:

---- readme_sect_examples_line_48 stdout ----
thread 'readme_sect_examples_line_48' panicked at 'Command failed:
"rustc" "/tmp/rust-skeptic.A9yLVWs4TK3g/test.rs" "--verbose" "--crate-type=bin" "--edition=2018" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps" "--target" "x86_64-unknown-linux-gnu" "--extern" "rand=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand-11a629c517e0d615.rlib" "--extern" "libsignal_protocol_sys=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol_sys-e6a37ece1ca80418.rlib" "--extern" "parking_lot=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libparking_lot-f71ea958c392d2c7.rlib" "--extern" "libsignal_protocol=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol-44ab010664573201.rlib" "--extern" "failure_derive=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfailure_derive-776aa24062317f93.so" "--extern" "sha2=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsha2-17612fee1e57d958.rlib" "--extern" "cmake=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libcmake-1a38ef44d902da32.rlib" "--extern" "skeptic=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libskeptic-437d724cfcd96d09.rlib" "--extern" "hmac=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libhmac-45aeceedb4b07843.rlib" "--extern" "lock_api=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblock_api-11780acf3615fb0b.rlib" "--extern" "failure=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfailure-863559f980b9bcdf.rlib" "-o" "/tmp/rust-skeptic.A9yLVWs4TK3g/out.exe"', /home/michael/.cargo/registry/src/github.com-1ecc6299db9ec823/skeptic-0.13.4/lib.rs:855:13
note: Run with `RUST_BACKTRACE=1` environment variable to display a backtrace.

---- readme_sect_examples_line_17 stdout ----
thread 'readme_sect_examples_line_17' panicked at 'Command failed:
"rustc" "/tmp/rust-skeptic.ajVOEidneULS/test.rs" "--verbose" "--crate-type=bin" "--edition=2018" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps" "--target" "x86_64-unknown-linux-gnu" "--extern" "cmake=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libcmake-1a38ef44d902da32.rlib" "--extern" "libsignal_protocol_sys=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol_sys-e6a37ece1ca80418.rlib" "--extern" "failure=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfailure-863559f980b9bcdf.rlib" "--extern" "failure_derive=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfailure_derive-776aa24062317f93.so" "--extern" "hmac=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libhmac-45aeceedb4b07843.rlib" "--extern" "sha2=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsha2-17612fee1e57d958.rlib" "--extern" "skeptic=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libskeptic-437d724cfcd96d09.rlib" "--extern" "parking_lot=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libparking_lot-f71ea958c392d2c7.rlib" "--extern" "libsignal_protocol=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol-44ab010664573201.rlib" "--extern" "lock_api=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblock_api-11780acf3615fb0b.rlib" "--extern" "rand=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand-11a629c517e0d615.rlib" "-o" "/tmp/rust-skeptic.ajVOEidneULS/out.exe"', /home/michael/.cargo/registry/src/github.com-1ecc6299db9ec823/skeptic-0.13.4/lib.rs:855:13

---- readme_sect_examples_line_27 stdout ----
thread 'readme_sect_examples_line_27' panicked at 'Command failed:
"rustc" "/tmp/rust-skeptic.rU5bHVsv3t5n/test.rs" "--verbose" "--crate-type=bin" "--edition=2018" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug" "-L" "/home/michael/Documents/libsignal-protocol-rs/target/debug/deps" "--target" "x86_64-unknown-linux-gnu" "--extern" "failure=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfailure-863559f980b9bcdf.rlib" "--extern" "lock_api=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblock_api-11780acf3615fb0b.rlib" "--extern" "failure_derive=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libfailure_derive-776aa24062317f93.so" "--extern" "rand=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/librand-11a629c517e0d615.rlib" "--extern" "libsignal_protocol=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol-44ab010664573201.rlib" "--extern" "sha2=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libsha2-17612fee1e57d958.rlib" "--extern" "libsignal_protocol_sys=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/liblibsignal_protocol_sys-e6a37ece1ca80418.rlib" "--extern" "hmac=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libhmac-45aeceedb4b07843.rlib" "--extern" "skeptic=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libskeptic-437d724cfcd96d09.rlib" "--extern" "cmake=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libcmake-1a38ef44d902da32.rlib" "--extern" "parking_lot=/home/michael/Documents/libsignal-protocol-rs/target/debug/deps/libparking_lot-f71ea958c392d2c7.rlib" "-o" "/tmp/rust-skeptic.rU5bHVsv3t5n/out.exe"', /home/michael/.cargo/registry/src/github.com-1ecc6299db9ec823/skeptic-0.13.4/lib.rs:855:13


failures:
    readme_sect_examples_line_17
    readme_sect_examples_line_27
    readme_sect_examples_line_48

test result: FAILED. 0 passed; 3 failed; 0 ignored; 0 measured; 0 filtered out

error: test failed, to rerun pass '-p libsignal-protocol --test skeptic'

The main detail from that output is

/usr/bin/ld: cannot find -lsignal-protocol-c

In particular, I know my *-sys crate's build script tells cargo to add /home/michael/Documents/libsignal-protocol-rs/target/debug/build/libsignal-protocol-sys-ae980dfaf57dd706/out/lib to the library search path, but I can't see a -L /home/michael/.../out/lib argument in the failed rustc command.

[Michael-F-Bryan]

It looks like the command to rustc is constructed here.

This comment is interesting...

// OK, here's where a bunch of magic happens using assumptions
// about cargo internals. We are going to use rustc to compile
// the examples, but to do that we've got to tell it where to
// look for the rlibs with the -L flag, and what their names
// are with the --extern flag. This is going to involve
// parsing fingerprints out of the lockfile and looking them
// up in the fingerprint file.

We add the rlib dependencies later on, but it doesn't look like anything else is done for discovering dependencies. Is there any easy way to ask cargo for the -L paths so we can add them to the command?

[budziq]

Hi @Michael-F-Bryan nice to hear from you!

Is there any easy way to ask cargo for the -L paths

Unfortunately there is no fool proof way to ask cargo for the paths at the moment without actually invoking the full cargo build. I'm still holding my breath for the full cargo build plan support rust-lang/cargo#5579 (but it's basically blocked on fact that build.rs can execute arbitrary code and alter the link flags). Or cargo being split into reusable libraries (recently mentioned in blog posts otherwise I need to go deeper in cargo re-implementation rabbit hole here)

On the other hand I've experimented with direct cargo invocation with enormous performance penalty due to cargo instances locking on project root dir. As far as I remember @brson had similar idea recently, maybe he had more success.

[Michael-F-Bryan]

Thanks for the link @budziq. I had a look through the related issues and found the build-plan crate on crates.io for reading the output from cargo build --build-plan -Z unstable-options, but it doesn't look like there's anything related to linking in native libraries...

---

I did a bit of digging and found the file where build.rs output goes.

$ tail target/debug/build/libsignal-protocol-sys-ae980dfaf57dd706/output
...
cargo:root=/home/michael/Documents/libsignal-protocol-rs/target/debug/build/libsignal-protocol-sys-ae980dfaf57dd706/out
cargo:rustc-link-search=native=/home/michael/Documents/libsignal-protocol-rs/target/debug/build/libsignal-protocol-sys-ae980dfaf57dd706/out
cargo:rustc-link-search=native=/home/michael/Documents/libsignal-protocol-rs/target/debug/build/libsignal-protocol-sys-ae980dfaf57dd706/out/lib
cargo:rustc-link-lib=signal-protocol-c

How hacky would it be to look for the build ouput files which correspond to our dependencies (i'm guessing we have access to the name and hash?) and then interpret them as cargo would?

I'm surprised using cargo for this is a performance problem! I might play around with it myself and see if I can find an easier way.

[budziq]

(i'm guessing we have access to the name and hash?) and then interpret them as cargo would?

Skeptic is already re-implementing cargo functionality to some extent already

How hacky would it be to look for the build ouput files which correspond to our dependencies

Very ;) but I'll try to tackle it if I'm able find some time (no promises in the near future though). In the mean time would you be able to provide me with a minimal reproducible example (some stale PR to your repo maybe) for me to tinker with in spare time?

[brson]

Not to discourage any short-term solutions to this, but I'm still of the opinion that the way to solve all these problems is to just use cargo. I mentioned some progress #18 (comment), but dropped work on it for other things. It is like 80% done though, and includes several compile-time performance mitigations.

I'm sorry I've not followed through on that, but this is at least a reminder.

I'm afraid that if this mess isn't solved soon that some better solution will displace skeptic.

[Michael-F-Bryan]

It looks like the cargo_metadata crate is able to read the output from build script execution and notes down the extra linker args.

In the mean time would you be able to provide me with a minimal reproducible example (some stale PR to your repo maybe) for me to tinker with in spare time?

I just tried to make a minimal repro which has a *-sys crate linking to a C "library" compiled from ``build.rs, then with a "safe" wrapper that also invokes skeptic's tests. This is essentially the same setup as we have in libsignal-protocol-rs`, but it seems to work fine 😠

The original PR is whisperfish/libsignal-protocol-rs#35, so you could check out the better-readme branch (48f1323) if you want to see exactly what we're seeing.

EDIT: You can also see the failing travis build here