Can't build for musl on Linux

[Timmmm]

I'm trying to build something that uses rust-openssl on Ubuntu 16.04 using the -musl target.

cargo build --release --target=x86_64-unknown-linux-musl

First when I build it it tells me to export PKG_CONFIG_ALLOW_CROSS=1. Not sure why but whatever; I did it.

Unfortunately then it seems to have trouble finding the OpenSSL headers. I installed them with sudo apt install libssl-dev.

cargo:warning=/home/parallels/myapp/target/x86_64-unknown-linux-musl/release/build/openssl-sys-9bee6f02b4f3e608/out/expando.c:2:33: fatal error: openssl/opensslconf.h: No such file or directory

You can do export OPENSSL_DIR=/usr/include/x86_64-linux-gnu and then it finds the headers, however then you get this error:

thread 'main' panicked at 'OpenSSL library directory does not exist: /usr/include/x86_64-linux-gnu/lib', /home/parallels/.cargo/registry/src/git.luolix.top-1ecc6299db9ec823/openssl-sys-0.9.9/build.rs:55

[sfackler]

You can use OPENSSL_LIB_DIR and OPENSSL_INCLUDE_DIR when the directories are split like this.

[Timmmm]

Hmmm the problem is it looks for openssl/opensslconf.h and openssl/opensslv.h but those are in different paths in Ubuntu, for some insane reason:

/usr/include/x86_64-linux-gnu/openssl/opensslconf.h
/usr/include/openssl/opensslv.h

It works with the non-musl target though. Maybe I need to link /usr/include/x86_64-linux-musl/openssl to /usr/include/x86_64-linux-gnu/openssl?

[Timmmm]

Yeah that seemed to do the trick. Although now libssh2-sys won't compile because it includes openssl/sha.h and apparently doesn't use OPENSSL_INCLUDE_DIR. Ugh. Can't wait for someone to rewrite OpenSSL in Rust.

[sfackler]

I'm confused - if you're cross-compiling to MUSL, you'll probably need an OpenSSL cross-compiled for MUSL as well. If you're not cross-compiling, pkg-config will handle all of this configuration for you when using the normal Ubuntu OpenSSL install.

[Timmmm]

Ah yes good point. I give up!

[fourohfour]

Note to anyone who comes across an error like this in the future - I was able to get this to work by building openssl-1.0.2l from source. Make sure that whatever path you give to ./config --openssldir={path} * when building openssl, you also export as the environment variable OPENSSL_DIR for the rust-openssl ** build. It might be necessary to point OPENSSL_INCLUDE_DIR and OPENSSL_LIB_DIR as well, but normally rust-openssl finds what it needs without issues.

• Docs on building OpenSSL from source

* /usr/local/ssl worked well for me.

** or perhaps a crate that depends it such as cargo

[tobias47n9e]

Confirming that same error happens on Ubuntu 17.10 with openssl-sys v0.9.27.

[parasyte]

I just landed on this ticket looking for a way to build native-tls with MUSL. What worked for me was building in clux/muslrust

[sztomi]

@parasyte thank you so much for mentioning that here, works like a charm.

[ctopher7]

@parasyte thanks for saving my life. Been searching to compile my app with the rust official image and keep crashing on openssl. This image works like a charm

[Ujang360]

I solved this with openssl = { version = "=0.10.33", features = ["vendored"] }