Auto merge of rust-lang#103075 - SUPERCILEX:miri-metadata, r=thomcc

Support DirEntry metadata calls in miri

This should work as it uses lstat64 which is supported here: ~https://github.com/rust-lang/miri/blob/d9ad25ee4bbd9364c498959cdc82b5fa6c41e63c/src/shims/unix/macos/foreign_items.rs#L42~ just noticed that's macos, linux would be using statx: https://github.com/rust-lang/miri/blob/86f0e63b21721fe2c14608644f467b9cb21945eb/src/shims/unix/linux/foreign_items.rs#L112

The failing syscall is `dirfd`, so maybe that should actually be added to the shims?

Author: bors

std/src/sys/unix/fs.rs

@@ -674,7 +674,10 @@ impl DirEntry {
         self.file_name_os_str().to_os_string()
     }
 
-    #[cfg(any(target_os = "linux", target_os = "emscripten", target_os = "android"))]
+    #[cfg(all(
+        any(target_os = "linux", target_os = "emscripten", target_os = "android"),
+        not(miri)
+    ))]
     pub fn metadata(&self) -> io::Result<FileAttr> {
         let fd = cvt(unsafe { dirfd(self.dir.dirp.0) })?;
         let name = self.name_cstr().as_ptr();
@@ -695,7 +698,10 @@ impl DirEntry {
         Ok(FileAttr::from_stat64(stat))
     }
 
-    #[cfg(not(any(target_os = "linux", target_os = "emscripten", target_os = "android")))]
+    #[cfg(any(
+        not(any(target_os = "linux", target_os = "emscripten", target_os = "android")),
+        miri
+    ))]
     pub fn metadata(&self) -> io::Result<FileAttr> {
         lstat(&self.path())
     }