diff --git a/.cirrus.yml b/.cirrus.yml
index 7ce3b932ba084..ff3b80f7f4fc1 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -7,9 +7,13 @@ task:
     - name: nightly freebsd-14
       freebsd_instance:
         image: freebsd-14-0-release-amd64-ufs
-    - name: nightly freebsd-15
-      freebsd_instance:
-        image_family: freebsd-15-0-snap
+    # Temporarily disable CI on FreeBSD 15.0-CURRENT until the libmd solib
+    # fallout is cleaned up.
+    # FIXME https://github.com/rust-lang/libc/issues/3967
+    # https://github.com/rust-lang/libc/issues/3967
+    #- name: nightly freebsd-15
+    # freebsd_instance:
+    # image_family: freebsd-15-0-snap
   setup_script:
     - pkg install -y libnghttp2 curl
     - curl https://sh.rustup.rs -sSf --output rustup.sh
diff --git a/libc-test/build.rs b/libc-test/build.rs
index fb779daecc123..dfa6185195dbc 100644
--- a/libc-test/build.rs
+++ b/libc-test/build.rs
@@ -4834,6 +4834,7 @@ fn test_haiku(target: &str) {
                "libutil.h",
                "link.h",
                "pty.h",
+               "stdlib.h",
                "stringlist.h",
                "sys/link_elf.h",
     }
diff --git a/libc-test/semver/apple.txt b/libc-test/semver/apple.txt
index 69166efd65e81..11f26658c2a47 100644
--- a/libc-test/semver/apple.txt
+++ b/libc-test/semver/apple.txt
@@ -455,6 +455,7 @@ F_SPECULATIVE_READ
 F_TEST
 F_THAW_FS
 F_TLOCK
+F_TRANSFEREXTENTS
 F_TRIM_ACTIVE_FILE
 F_ULOCK
 F_UNLCK
diff --git a/libc-test/semver/linux-musl.txt b/libc-test/semver/linux-musl.txt
index e873cb21d0491..b775cec7182d9 100644
--- a/libc-test/semver/linux-musl.txt
+++ b/libc-test/semver/linux-musl.txt
@@ -80,6 +80,8 @@ getloadavg
 lio_listio
 ntptimeval
 open_wmemstream
+posix_spawn_file_actions_addchdir_np
+posix_spawn_file_actions_addfchdir_np
 preadv2
 preadv64
 prlimit
diff --git a/src/unix/bsd/apple/mod.rs b/src/unix/bsd/apple/mod.rs
index c204f1db507fe..804bd89b5c4e8 100644
--- a/src/unix/bsd/apple/mod.rs
+++ b/src/unix/bsd/apple/mod.rs
@@ -3618,6 +3618,7 @@ pub const F_PUNCHHOLE: ::c_int = 99;
 pub const F_TRIM_ACTIVE_FILE: ::c_int = 100;
 pub const F_SPECULATIVE_READ: ::c_int = 101;
 pub const F_GETPATH_NOFIRMLINK: ::c_int = 102;
+pub const F_TRANSFEREXTENTS: ::c_int = 110;
 
 pub const F_ALLOCATECONTIG: ::c_uint = 0x02;
 pub const F_ALLOCATEALL: ::c_uint = 0x04;
diff --git a/src/unix/haiku/mod.rs b/src/unix/haiku/mod.rs
index 4dc931cd047d9..3a226e6696405 100644
--- a/src/unix/haiku/mod.rs
+++ b/src/unix/haiku/mod.rs
@@ -2133,6 +2133,10 @@ extern "C" {
         >,
         data: *mut ::c_void,
     ) -> ::c_int;
+
+    pub fn arc4random() -> u32;
+    pub fn arc4random_uniform(upper_bound: u32) -> u32;
+    pub fn arc4random_buf(buf: *mut ::c_void, n: ::size_t);
 }
 
 #[link(name = "gnu")]
diff --git a/src/unix/linux_like/linux/musl/mod.rs b/src/unix/linux_like/linux/musl/mod.rs
index 72bd335360b8e..14e1e6d3bfd0f 100644
--- a/src/unix/linux_like/linux/musl/mod.rs
+++ b/src/unix/linux_like/linux/musl/mod.rs
@@ -983,6 +983,17 @@ extern "C" {
 
     pub fn dirname(path: *mut ::c_char) -> *mut ::c_char;
     pub fn basename(path: *mut ::c_char) -> *mut ::c_char;
+
+    // Added in `musl` 1.1.24
+    pub fn posix_spawn_file_actions_addchdir_np(
+        actions: *mut ::posix_spawn_file_actions_t,
+        path: *const ::c_char,
+    ) -> ::c_int;
+    // Added in `musl` 1.1.24
+    pub fn posix_spawn_file_actions_addfchdir_np(
+        actions: *mut ::posix_spawn_file_actions_t,
+        fd: ::c_int,
+    ) -> ::c_int;
 }
 
 // Alias <foo> to <foo>64 to mimic glibc's LFS64 support
diff --git a/src/unix/newlib/rtems/mod.rs b/src/unix/newlib/rtems/mod.rs
index 36f4820c92f4f..031754950e6c1 100644
--- a/src/unix/newlib/rtems/mod.rs
+++ b/src/unix/newlib/rtems/mod.rs
@@ -137,5 +137,7 @@ extern "C" {
         clock_id: ::clockid_t,
     ) -> ::c_int;
 
+    pub fn getentropy(buf: *mut ::c_void, buflen: ::size_t) -> ::c_int;
+
     pub fn setgroups(ngroups: ::c_int, grouplist: *const ::gid_t) -> ::c_int;
 }