Fixup: respond to feedback from @tgross35

Author: asomers

libc-test/build.rs

@@ -2674,7 +2674,7 @@ fn test_freebsd(target: &str) {
     cfg.volatile_item(|i| {
         use ctest::VolatileItemKind::*;
         match i {
-            // aio_buf is a volatile void** but since we cannot express that in
+            // aio_buf is a volatile void* but since we cannot express that in
             // Rust types, we have to explicitly tell the checker about it here:
             StructField(ref n, ref f) if n == "aiocb" && f == "aio_buf" => true,
             _ => false,

src/unix/bsd/freebsdlike/freebsd/mod.rs

@@ -237,7 +237,8 @@ impl ::Clone for devstat_select_mode {
 
 s! {
     pub struct __c_anonymous_sigev_thread {
-        pub _function: *mut ::c_void, // Actually a function pointer
+        pub _function: Option<extern "C" fn(::sigval) -> *mut ::c_void>,
+        //pub _function: *mut ::c_void, // Actually a function pointer
         pub _attribute: *mut ::pthread_attr_t,
     }
 
@@ -1340,20 +1341,24 @@ s! {
 }
 
 s_no_extra_traits! {
+    #[cfg_attr(feature = "extra_traits", derive(Debug))]
+    pub struct __aiocb_private {
+        status: ::c_long,
+        error: ::c_long,
+        spare: *mut ::c_void
+    }
+
     #[cfg_attr(feature = "extra_traits", derive(Debug))]
     pub struct aiocb {
         pub aio_fildes: ::c_int,
         pub aio_offset: ::off_t,
         pub aio_buf: *mut ::c_void,
         pub aio_nbytes: ::size_t,
-        __unused1: [::c_int; 2],
-        __unused2: *mut ::c_void,
+        __spare__: [::c_int; 2],
+        __spare2__: *mut ::c_void,
         pub aio_lio_opcode: ::c_int,
         pub aio_reqprio: ::c_int,
-        // unused 3 through 5 are the __aiocb_private structure
-        __unused3: ::c_long,
-        __unused4: ::c_long,
-        __unused5: *mut ::c_void,
+        _aiocb_private: __aiocb_private,
         pub aio_sigevent: sigevent,
     }
 

src/unix/linux_like/linux/gnu/mod.rs

@@ -506,9 +506,10 @@ s_no_extra_traits! {
         __policy: ::c_int,
         __error_code: ::c_int,
         __return_value: ::ssize_t,
+        // FIXME(off64): visible fields depend on __USE_FILE_OFFSET64
         pub aio_offset: off_t,
         #[cfg(all(not(target_arch = "x86_64"), target_pointer_width = "32"))]
-        __unused1: [::c_char; 4],
+        __pad: [::c_char; 4],
         __glibc_reserved: [::c_char; 32],
     }
 }

src/unix/linux_like/linux/musl/mod.rs

@@ -414,6 +414,7 @@ s_no_extra_traits! {
         pub aio_offset: off_t,
         __next: *mut ::c_void,
         __prev: *mut ::c_void,
+        // FIXME(ctest): length should be `32 - 2 * core::mem::size_of::<*const ()>()`
         #[cfg(target_pointer_width = "32")]
         __dummy4: [::c_char; 24],
         #[cfg(target_pointer_width = "64")]

src/unix/linux_like/mod.rs

@@ -13,7 +13,7 @@ missing! {
 
 s! {
     pub struct __c_anonymous_sigev_thread {
-        pub _function: *mut ::c_void, // Actually a function pointer
+        pub _function: Option<extern "C" fn(::sigval) -> *mut ::c_void>,
         pub _attribute: *mut ::pthread_attr_t,
     }