commit c31d51a04fc53f4bff403246982efe77bfa17da1
author Junho Choi <1229714+junhochoi@users.noreply.github.com> Mon Dec 02 15:26:43 2019 -0800
committer Alessandro Ghedini <alessandro@ghedini.me> Mon Dec 02 23:26:43 2019 +0000
tree cb1e8a1680e4b0eec76969a27bea19db40ff1b92
parent 36efb4325325ea10748c17bfb9c08dfd40e69a05

build: fix cdylib build with --no-default-features on macOS

Seems like when you build dylib in MacOS it will try to find
all symbols defined by default, resulting cdylib link failing due to
missing boringssl library. Add a linker option to allow building
dylib without finding undefined symbols.

Ref: https://glandium.org/blog/?p=2764

Fixes #238. 

src/build.rs

diff --git a/src/build.rs b/src/build.rs
index 8cfd691..c1ab4e4 100644
--- a/src/build.rs
+++ b/src/build.rs
@@ -180,6 +180,11 @@
         println!("cargo:rustc-link-lib=static=ssl");
     }
 
+    // MacOS: Allow cdylib to link with undefined symbols
+    if cfg!(target_os = "macos") {
+        println!("cargo:rustc-cdylib-link-arg=-Wl,-undefined,dynamic_lookup");
+    }
+
     if cfg!(feature = "pkg-config-meta") {
         write_pkg_config();
     }