diff --git a/src/librustc_back/target/haiku_base.rs b/src/librustc_back/target/haiku_base.rs
index bfdc9faaa8a..8e7f463563c 100644
--- a/src/librustc_back/target/haiku_base.rs
+++ b/src/librustc_back/target/haiku_base.rs
@@ -16,9 +16,10 @@ pub fn opts() -> TargetOptions {
         linker: "cc".to_string(),
         dynamic_linking: true,
         executables: true,
-        has_rpath: true,
+        has_rpath: false,
         target_family: Some("unix".to_string()),
         linker_is_gnu: true,
+        no_integrated_as: true,
         .. Default::default()
     }
 }
diff --git a/src/librustc_data_structures/flock.rs b/src/librustc_data_structures/flock.rs
index 26417e3ba7c..32f0fd41997 100644
--- a/src/librustc_data_structures/flock.rs
+++ b/src/librustc_data_structures/flock.rs
@@ -113,6 +113,7 @@ pub struct flock {
             pub l_sysid: libc::c_int,
         }
 
+        pub const F_RDLCK: libc::c_short = 0x0040;
         pub const F_UNLCK: libc::c_short = 0x0200;
         pub const F_WRLCK: libc::c_short = 0x0400;
         pub const F_SETLK: libc::c_int = 0x0080;
diff --git a/src/libunwind/build.rs b/src/libunwind/build.rs
index 9b8099d55a0..be9aa6c5d40 100644
--- a/src/libunwind/build.rs
+++ b/src/libunwind/build.rs
@@ -39,5 +39,7 @@ fn main() {
         println!("cargo:rustc-link-lib=static-nobundle=pthread");
     } else if target.contains("fuchsia") {
         println!("cargo:rustc-link-lib=unwind");
+    } else if target.contains("haiku") {
+        println!("cargo:rustc-link-lib=gcc_s");
     }
 }