Auto merge of #2993 - zhaixiaojuan:LA-add-ucontext-clone_args, r=JohnTitor

Add ucontext and clone_args for loongarch64

Author: bors

src/unix/linux_like/linux/gnu/b64/loongarch64/align.rs

@@ -5,3 +5,36 @@ s_no_extra_traits! {
         priv_: [f64; 4]
     }
 }
+
+s! {
+    pub struct ucontext_t {
+        pub uc_flags: ::c_ulong,
+        pub uc_link: *mut ucontext_t,
+        pub uc_stack: ::stack_t,
+        pub uc_sigmask: ::sigset_t,
+        pub uc_mcontext: mcontext_t,
+    }
+
+    #[repr(align(16))]
+    pub struct mcontext_t {
+        pub sc_pc: ::c_ulonglong,
+        pub sc_regs: [::c_ulonglong; 32],
+        pub sc_flags: ::c_ulong,
+        pub sc_extcontext: [u64; 0],
+    }
+
+    #[repr(align(8))]
+    pub struct clone_args {
+        pub flags: ::c_ulonglong,
+        pub pidfd: ::c_ulonglong,
+        pub child_tid: ::c_ulonglong,
+        pub parent_tid: ::c_ulonglong,
+        pub exit_signal: ::c_ulonglong,
+        pub stack: ::c_ulonglong,
+        pub stack_size: ::c_ulonglong,
+        pub tls: ::c_ulonglong,
+        pub set_tid: ::c_ulonglong,
+        pub set_tid_size: ::c_ulonglong,
+        pub cgroup: ::c_ulonglong,
+    }
+}