3 use spec::{LinkArgs, TargetOptions};
5 pub fn opts() -> TargetOptions {
6 // ELF TLS is only available in macOS 10.7+. If you try to compile for 10.6
7 // either the linker will complain if it is used or the binary will end up
8 // segfaulting at runtime when run on 10.6. Rust by default supports macOS
9 // 10.7+, but there is a standard environment variable,
10 // MACOSX_DEPLOYMENT_TARGET, which is used to signal targeting older
11 // versions of macOS. For example compiling on 10.10 with
12 // MACOSX_DEPLOYMENT_TARGET set to 10.6 will cause the linker to generate
13 // warnings about the usage of ELF TLS.
15 // Here we detect what version is being requested, defaulting to 10.7. ELF
16 // TLS is flagged as enabled if it looks to be supported.
17 let deployment_target = env::var("MACOSX_DEPLOYMENT_TARGET").ok();
18 let version = deployment_target.as_ref().and_then(|s| {
19 let mut i = s.splitn(2, '.');
20 i.next().and_then(|a| i.next().map(|b| (a, b)))
21 }).and_then(|(a, b)| {
22 a.parse::<u32>().and_then(|a| b.parse::<u32>().map(|b| (a, b))).ok()
23 }).unwrap_or((10, 7));
26 // macOS has -dead_strip, which doesn't rely on function_sections
27 function_sections: false,
28 dynamic_linking: true,
30 target_family: Some("unix".to_string()),
33 dll_prefix: "lib".to_string(),
34 dll_suffix: ".dylib".to_string(),
35 archive_format: "bsd".to_string(),
36 pre_link_args: LinkArgs::new(),
37 has_elf_tls: version >= (10, 7),
38 abi_return_struct_as_int: true,
39 emit_debug_gdb_scripts: false,