| // Copyright 2015 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| extern crate gcc; |
| extern crate build_helper; |
| |
| use std::process::Command; |
| use std::env; |
| use std::path::{PathBuf, Path}; |
| |
| use build_helper::output; |
| |
| fn main() { |
| println!("cargo:rustc-cfg=cargobuild"); |
| |
| let target = env::var("TARGET").unwrap(); |
| let llvm_config = env::var_os("LLVM_CONFIG") |
| .map(PathBuf::from) |
| .unwrap_or_else(|| { |
| if let Some(dir) = env::var_os("CARGO_TARGET_DIR") |
| .map(PathBuf::from) { |
| let to_test = dir.parent() |
| .unwrap() |
| .parent() |
| .unwrap() |
| .join(&target) |
| .join("llvm/bin/llvm-config"); |
| if Command::new(&to_test).output().is_ok() { |
| return to_test; |
| } |
| } |
| PathBuf::from("llvm-config") |
| }); |
| |
| println!("cargo:rerun-if-changed={}", llvm_config.display()); |
| |
| // Test whether we're cross-compiling LLVM. This is a pretty rare case |
| // currently where we're producing an LLVM for a different platform than |
| // what this build script is currently running on. |
| // |
| // In that case, there's no guarantee that we can actually run the target, |
| // so the build system works around this by giving us the LLVM_CONFIG for |
| // the host platform. This only really works if the host LLVM and target |
| // LLVM are compiled the same way, but for us that's typically the case. |
| // |
| // We *want* detect this cross compiling situation by asking llvm-config |
| // what it's host-target is. If that's not the TARGET, then we're cross |
| // compiling. Unfortunately `llvm-config` seems either be buggy, or we're |
| // misconfiguring it, because the `i686-pc-windows-gnu` build of LLVM will |
| // report itself with a `--host-target` of `x86_64-pc-windows-gnu`. This |
| // tricks us into thinking we're doing a cross build when we aren't, so |
| // havoc ensues. |
| // |
| // In any case, if we're cross compiling, this generally just means that we |
| // can't trust all the output of llvm-config becaues it might be targeted |
| // for the host rather than the target. As a result a bunch of blocks below |
| // are gated on `if !is_crossed` |
| let target = env::var("TARGET").unwrap(); |
| let host = env::var("HOST").unwrap(); |
| let is_crossed = target != host; |
| |
| let optional_components = ["x86", "arm", "aarch64", "mips", "powerpc", "pnacl"]; |
| |
| // FIXME: surely we don't need all these components, right? Stuff like mcjit |
| // or interpreter the compiler itself never uses. |
| let required_components = &["ipo", |
| "bitreader", |
| "bitwriter", |
| "linker", |
| "asmparser", |
| "mcjit", |
| "interpreter", |
| "instrumentation"]; |
| |
| let components = output(Command::new(&llvm_config).arg("--components")); |
| let mut components = components.split_whitespace().collect::<Vec<_>>(); |
| components.retain(|c| optional_components.contains(c) || required_components.contains(c)); |
| |
| for component in required_components { |
| if !components.contains(component) { |
| panic!("require llvm component {} but wasn't found", component); |
| } |
| } |
| |
| for component in components.iter() { |
| println!("cargo:rustc-cfg=llvm_component=\"{}\"", component); |
| } |
| |
| // Link in our own LLVM shims, compiled with the same flags as LLVM |
| let mut cmd = Command::new(&llvm_config); |
| cmd.arg("--cxxflags"); |
| let cxxflags = output(&mut cmd); |
| let mut cfg = gcc::Config::new(); |
| for flag in cxxflags.split_whitespace() { |
| // Ignore flags like `-m64` when we're doing a cross build |
| if is_crossed && flag.starts_with("-m") { |
| continue; |
| } |
| cfg.flag(flag); |
| } |
| |
| for component in &components[..] { |
| let mut flag = String::from("-DLLVM_COMPONENT_"); |
| flag.push_str(&component.to_uppercase()); |
| cfg.flag(&flag); |
| } |
| |
| cfg.file("../rustllvm/PassWrapper.cpp") |
| .file("../rustllvm/RustWrapper.cpp") |
| .file("../rustllvm/ArchiveWrapper.cpp") |
| .cpp(true) |
| .cpp_link_stdlib(None) // we handle this below |
| .compile("librustllvm.a"); |
| |
| // Link in all LLVM libraries, if we're uwring the "wrong" llvm-config then |
| // we don't pick up system libs because unfortunately they're for the host |
| // of llvm-config, not the target that we're attempting to link. |
| let mut cmd = Command::new(&llvm_config); |
| cmd.arg("--libs"); |
| if !is_crossed { |
| cmd.arg("--system-libs"); |
| } |
| cmd.args(&components[..]); |
| |
| for lib in output(&mut cmd).split_whitespace() { |
| let name = if lib.starts_with("-l") { |
| &lib[2..] |
| } else if lib.starts_with("-") { |
| &lib[1..] |
| } else if Path::new(lib).exists() { |
| // On MSVC llvm-config will print the full name to libraries, but |
| // we're only interested in the name part |
| let name = Path::new(lib).file_name().unwrap().to_str().unwrap(); |
| name.trim_right_matches(".lib") |
| } else if lib.ends_with(".lib") { |
| // Some MSVC libraries just come up with `.lib` tacked on, so chop |
| // that off |
| lib.trim_right_matches(".lib") |
| } else { |
| continue |
| }; |
| |
| // Don't need or want this library, but LLVM's CMake build system |
| // doesn't provide a way to disable it, so filter it here even though we |
| // may or may not have built it. We don't reference anything from this |
| // library and it otherwise may just pull in extra dependencies on |
| // libedit which we don't want |
| if name == "LLVMLineEditor" { |
| continue |
| } |
| |
| let kind = if name.starts_with("LLVM") { |
| "static" |
| } else { |
| "dylib" |
| }; |
| println!("cargo:rustc-link-lib={}={}", kind, name); |
| } |
| |
| // LLVM ldflags |
| // |
| // If we're a cross-compile of LLVM then unfortunately we can't trust these |
| // ldflags (largely where all the LLVM libs are located). Currently just |
| // hack around this by replacing the host triple with the target and pray |
| // that those -L directories are the same! |
| let mut cmd = Command::new(&llvm_config); |
| cmd.arg("--ldflags"); |
| for lib in output(&mut cmd).split_whitespace() { |
| if lib.starts_with("-LIBPATH:") { |
| println!("cargo:rustc-link-search=native={}", &lib[9..]); |
| } else if is_crossed { |
| if lib.starts_with("-L") { |
| println!("cargo:rustc-link-search=native={}", |
| lib[2..].replace(&host, &target)); |
| } |
| } else if lib.starts_with("-l") { |
| println!("cargo:rustc-link-lib={}", &lib[2..]); |
| } else if lib.starts_with("-L") { |
| println!("cargo:rustc-link-search=native={}", &lib[2..]); |
| } |
| } |
| |
| // C++ runtime library |
| if !target.contains("msvc") { |
| if let Some(s) = env::var_os("LLVM_STATIC_STDCPP") { |
| assert!(!cxxflags.contains("stdlib=libc++")); |
| let path = PathBuf::from(s); |
| println!("cargo:rustc-link-search=native={}", |
| path.parent().unwrap().display()); |
| println!("cargo:rustc-link-lib=static=stdc++"); |
| } else if cxxflags.contains("stdlib=libc++") { |
| println!("cargo:rustc-link-lib=c++"); |
| } else { |
| println!("cargo:rustc-link-lib=stdc++"); |
| } |
| } |
| } |
