3 use crate::spec::{FramePointer, LldFlavor, SplitDebuginfo, TargetOptions};
5 pub fn opts(os: &str) -> 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 version = macos_deployment_target();
21 vendor: "apple".to_string(),
22 // macOS has -dead_strip, which doesn't rely on function_sections
23 function_sections: false,
24 dynamic_linking: true,
27 families: vec!["unix".to_string()],
29 dwarf_version: Some(2),
30 frame_pointer: FramePointer::Always,
32 dll_suffix: ".dylib".to_string(),
33 archive_format: "darwin".to_string(),
34 has_elf_tls: version >= (10, 7),
35 abi_return_struct_as_int: true,
36 emit_debug_gdb_scripts: false,
37 eh_frame_header: false,
38 lld_flavor: LldFlavor::Ld64,
40 // The historical default for macOS targets is to run `dsymutil` which
41 // generates a packed version of debuginfo split from the main file.
42 split_debuginfo: SplitDebuginfo::Packed,
44 // This environment variable is pretty magical but is intended for
45 // producing deterministic builds. This was first discovered to be used
46 // by the `ar` tool as a way to control whether or not mtime entries in
47 // the archive headers were set to zero or not. It appears that
48 // eventually the linker got updated to do the same thing and now reads
49 // this environment variable too in recent versions.
51 // For some more info see the commentary on #47086
52 link_env: vec![("ZERO_AR_DATE".to_string(), "1".to_string())],
58 fn deployment_target(var_name: &str) -> Option<(u32, u32)> {
59 let deployment_target = env::var(var_name).ok();
62 .and_then(|s| s.split_once('.'))
63 .and_then(|(a, b)| a.parse::<u32>().and_then(|a| b.parse::<u32>().map(|b| (a, b))).ok())
66 fn macos_deployment_target() -> (u32, u32) {
67 deployment_target("MACOSX_DEPLOYMENT_TARGET").unwrap_or((10, 7))
70 pub fn macos_llvm_target(arch: &str) -> String {
71 let (major, minor) = macos_deployment_target();
72 format!("{}-apple-macosx{}.{}.0", arch, major, minor)
75 pub fn macos_link_env_remove() -> Vec<String> {
76 let mut env_remove = Vec::with_capacity(2);
77 // Remove the `SDKROOT` environment variable if it's clearly set for the wrong platform, which
78 // may occur when we're linking a custom build script while targeting iOS for example.
79 if let Ok(sdkroot) = env::var("SDKROOT") {
80 if sdkroot.contains("iPhoneOS.platform") || sdkroot.contains("iPhoneSimulator.platform") {
81 env_remove.push("SDKROOT".to_string())
84 // Additionally, `IPHONEOS_DEPLOYMENT_TARGET` must not be set when using the Xcode linker at
85 // "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ld",
86 // although this is apparently ignored when using the linker at "/usr/bin/ld".
87 env_remove.push("IPHONEOS_DEPLOYMENT_TARGET".to_string());
91 fn ios_deployment_target() -> (u32, u32) {
92 deployment_target("IPHONEOS_DEPLOYMENT_TARGET").unwrap_or((7, 0))
95 pub fn ios_llvm_target(arch: &str) -> String {
96 // Modern iOS tooling extracts information about deployment target
97 // from LC_BUILD_VERSION. This load command will only be emitted when
98 // we build with a version specific `llvm_target`, with the version
99 // set high enough. Luckily one LC_BUILD_VERSION is enough, for Xcode
100 // to pick it up (since std and core are still built with the fallback
101 // of version 7.0 and hence emit the old LC_IPHONE_MIN_VERSION).
102 let (major, minor) = ios_deployment_target();
103 format!("{}-apple-ios{}.{}.0", arch, major, minor)
106 pub fn ios_sim_llvm_target(arch: &str) -> String {
107 let (major, minor) = ios_deployment_target();
108 format!("{}-apple-ios{}.{}.0-simulator", arch, major, minor)