Cross building for armhf fails with "hidden symbol 'ZSTD_isError'" linker error

[MuratUrsavas]

Hi,

Thanks for this neat zstd library. I'm trying to use it in our software and was able to use it successfully for both aarch64 and amd64 architectures without a problem. But I also need it for armhf architecture and bumped to a build problem which I couldn't resolve.

Here's the build result for armhf cross compilation on amd64 machine (bindgen feature not enabled):

2024-06-21 05:56:05.115 ::    Compiling zstd-sys v2.0.11+zstd.1.5.6                                                                                            
2024-06-21 05:56:07.746 ::    Compiling zstd v0.13.1                                                                                                           
2024-06-21 05:56:08.022 ::    Compiling device-manager v0.1.0 (/var/root-project/parts/rust-services/build/device-manager)                                     
2024-06-21 05:56:51.627 :: error: linking with `arm-linux-gnueabihf-gcc` failed: exit status: 1                                                                
2024-06-21 05:56:51.628 ::   |                                                                                                                                 
2024-06-21 05:56:51.628 ::   = note: LC_ALL="C" PATH="/var/root-project/stage/opt/rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/bin:/var/root-project/stage/usr/bin:/var/root-project/stage/sbin:/var/root-project/stage/bin:/snap/snapcraft/11039/libexec/snapcraft:/snap/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/var/root-project/stage/opt/cargo/bin" VSLANG="1033" "arm-linux-gnueabihf-gcc" "/tmp/rustck0JY1g/symbols.o" "/var/root-project/parts/rust-services/build/target/armv7-unknown-linux-gnueabihf/release/deps/device_manager-22501b77a62423dd.device_manager.c0b6ae309808d4c8-cgu.0.rcgu.o" "-Wl,--as-needed" "-L" "/var/root-project/parts/rust-services/build/target/armv7-unknown-linux-gnueabihf/release/deps" "-L" "/var/root-project/parts/rust-services/build/target/release/deps" "-L" "/var/root-project/stage/usr/lib/arm-linux-gnueabihf" "-L" "/var/root-project/stage/var/root-project/stage/usr/lib/arm-linux-gnueabihf" "-L" "/var/root-project/stage/usr/lib/arm-linux-gnueabihf" "-L" "/var/root-project/parts/rust-services/build/target/armv7-unknown-linux-gnueabihf/release/build/zstd-sys-3a5fac7ca05b3e6a/out" "-L" "/var/root-project/stage/opt/rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/armv7-unknown-linux-gnueabihf/lib" "-Wl,-Bstatic" "/tmp/rustck0JY1g/libzstd_sys-e9558b8d5f899acd.rlib" "/var/root-project/stage/opt/rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/armv7-unknown-linux-gnueabihf/lib/libcompiler_builtins-ca98583dba9cbc39.rlib" "-Wl,-Bdynamic" "-lsystemd" "-ldbus-1" "-lssl" "-lcrypto" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "/var/root-project/stage/opt/rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/armv7-unknown-linux-gnueabihf/lib" "-o" "/var/root-project/parts/rust-services/build/target/armv7-unknown-linux-gnueabihf/release/deps/device_manager-22501b77a62423dd" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-Wl,--strip-debug" "-nodefaultlibs" "-Wl,-rpath-link,/var/root-project/stage/lib/arm-linux-gnueabihf/" "-Wl,-rpath-link,/var/root-project/stage/usr/lib/arm-linux-gnueabihf/" "-Wl,--allow-shlib-undefined"                     
2024-06-21 05:56:51.628 ::   = note: /usr/lib/gcc-cross/arm-linux-gnueabihf/11/../../../../arm-linux-gnueabihf/bin/ld: /var/root-project/parts/rust-services/build/target/armv7-unknown-linux-gnueabihf/release/deps/device_manager-22501b77a62423dd: hidden symbol `ZSTD_isError' in /tmp/rustck0JY1g/libzstd_sys-e9558b8d5f899acd.rlib(zstd_common.o) is referenced by DSO                                                                                                                   
2024-06-21 05:56:51.628 ::           /usr/lib/gcc-cross/arm-linux-gnueabihf/11/../../../../arm-linux-gnueabihf/bin/ld: final link failed: bad value            
2024-06-21 05:56:51.629 ::           collect2: error: ld returned 1 exit status                                                                                
2024-06-21 05:56:51.629 ::                                                                                                                                     
2024-06-21 05:56:51.629 ::                                                                                                                                     
2024-06-21 05:56:51.666 :: error: could not compile `device-manager` (bin "device-manager") due to 1 previous error

Note: If I cross build zstd-rs for armhf, everything is alright. The problem arises at linking time.

OS: Ubuntu 22.04
Rust: 1.79 stable for amd64 and armhf, Edition 2021

Regards,
/// Murat