add improper_ctypes_definitions lint

Cargo.toml

@@ -30,6 +30,7 @@ zero_ptr = "warn" # must allow on public constants due to cbindgen issue
 
 [workspace.lints.rust]
 dangling_pointers_from_temporaries = "deny"
+improper_ctypes_definitions = "deny"
 internal_features = "allow" # core_intrinsics and lang_items
 irrefutable_let_patterns = "deny"
 mismatched_lifetime_syntaxes = "deny"

src/header/arch_aarch64_user/mod.rs

@@ -16,7 +16,7 @@ pub struct user_fpsimd_struct {
 }
 
 pub type elf_greg_t = c_ulong;
-pub type elf_gregset_t = [c_ulong; 34];
+pub type elf_gregset_t = *mut [c_ulong; 34];
 pub type elf_fpregset_t = user_fpsimd_struct;
 
 #[unsafe(no_mangle)]

src/header/arch_x64_user/mod.rs

@@ -50,7 +50,7 @@ pub struct user_regs_struct {
 
 pub type elf_greg_t = c_ulong;
 
-pub type elf_gregset_t = [c_ulong; 27];
+pub type elf_gregset_t = *mut [c_ulong; 27];
 pub type elf_fpregset_t = user_fpregs_struct;
 #[repr(C)]
 pub struct user {

src/header/sys_procfs/mod.rs

@@ -59,7 +59,7 @@ pub struct elf_prpsinfo {
 }
 
 pub type psaddr_t = *mut c_void;
-pub type prgregset_t = elf_gregset_t;
+pub type prgregset_t = *mut elf_gregset_t;
 pub type prfpregset_t = elf_fpregset_t;
 pub type lwpid_t = pid_t;
 pub type prstatus_t = elf_prstatus;

src/header/unistd/mod.rs

@@ -282,11 +282,11 @@ pub extern "C" fn dup3(fildes: c_int, fildes2: c_int, flag: c_int) -> c_int {
 ///
 /// # Deprecation
 /// The `encrypt()` function was marked obsolescent in the Open Group Base Specifications Issue 8.
-#[deprecated]
+//#[deprecated]
 // #[unsafe(no_mangle)]
-pub extern "C" fn encrypt(block: [c_char; 64], edflag: c_int) {
-    unimplemented!();
-}
+//pub extern "C" fn encrypt(block: [c_char; 64], edflag: c_int) {
+//    unimplemented!();
+//}
 
 /// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/exec.html>.
 #[unsafe(no_mangle)]

src/lib.rs

@@ -88,8 +88,10 @@ pub extern "C" fn rust_eh_personality() {}
 #[cfg(not(test))]
 #[alloc_error_handler]
 #[linkage = "weak"]
+#[allow(improper_ctypes_definitions)]
 #[unsafe(no_mangle)]
 pub extern "C" fn rust_oom(layout: ::core::alloc::Layout) -> ! {
+    // Layout not FFI-safe?
     use core::fmt::Write;
 
     let mut w = platform::FileWriter::new(2);