actually this doesn't even affect doctests. nice.

2 files changed, 9 insertions, 18 deletions

diff --git a/library/std/src/ffi/os_str.rs b/library/std/src/ffi/os_str.rs
index a9907ae1034..43cecb19b14 100644
--- a/library/std/src/ffi/os_str.rs
+++ b/library/std/src/ffi/os_str.rs
@@ -110,14 +110,11 @@ impl crate::sealed::Sealed for OsString {}
 /// [conversions]: super#conversions
 #[cfg_attr(not(test), rustc_diagnostic_item = "OsStr")]
 #[stable(feature = "rust1", since = "1.0.0")]
-// FIXME:
 // `OsStr::from_inner` current implementation relies
 // on `OsStr` being layout-compatible with `Slice`.
-// When attribute privacy is implemented, `OsStr` should be annotated as `#[repr(transparent)]`.
-// Anyway, `OsStr` representation and layout are considered implementation details, are
-// not documented and must not be relied upon.
-// For now we just hide this from rustdoc, technically making our doc test builds rely on
-// unspecified layout assumptions. We are std, so we can get away with that.
+// However, `OsStr` layout is considered an implementation detail and must not be relied upon. We
+// want `repr(transparent)` but we don't want it to show up in rustdoc, so we hide it under
+// `cfg(doc)`. This is an ad-hoc implementation of attribute privacy.
 #[cfg_attr(not(doc), repr(transparent))]
 pub struct OsStr {
     inner: Slice,
diff --git a/library/std/src/path.rs b/library/std/src/path.rs
index ef5fc669037..5842c096f1a 100644
--- a/library/std/src/path.rs
+++ b/library/std/src/path.rs
@@ -1158,14 +1158,11 @@ impl FusedIterator for Ancestors<'_> {}
 /// Which method works best depends on what kind of situation you're in.
 #[cfg_attr(not(test), rustc_diagnostic_item = "PathBuf")]
 #[stable(feature = "rust1", since = "1.0.0")]
-// FIXME:
 // `PathBuf::as_mut_vec` current implementation relies
 // on `PathBuf` being layout-compatible with `Vec<u8>`.
-// When attribute privacy is implemented, `PathBuf` should be annotated as `#[repr(transparent)]`.
-// Anyway, `PathBuf` representation and layout are considered implementation detail, are
-// not documented and must not be relied upon.
-// For now we just hide this from rustdoc, technically making our doc test builds rely on
-// unspecified layout assumptions. We are std, so we can get away with that.
+// However, `PathBuf` layout is considered an implementation detail and must not be relied upon. We
+// want `repr(transparent)` but we don't want it to show up in rustdoc, so we hide it under
+// `cfg(doc)`. This is an ad-hoc implementation of attribute privacy.
 #[cfg_attr(not(doc), repr(transparent))]
 pub struct PathBuf {
     inner: OsString,
@@ -1986,14 +1983,11 @@ impl AsRef<OsStr> for PathBuf {
 /// ```
 #[cfg_attr(not(test), rustc_diagnostic_item = "Path")]
 #[stable(feature = "rust1", since = "1.0.0")]
-// FIXME:
 // `Path::new` current implementation relies
 // on `Path` being layout-compatible with `OsStr`.
-// When attribute privacy is implemented, `Path` should be annotated as `#[repr(transparent)]`.
-// Anyway, `Path` representation and layout are considered implementation detail, are
-// not documented and must not be relied upon.
-// For now we just hide this from rustdoc, technically making our doc test builds rely on
-// unspecified layout assumptions. We are std, so we can get away with that.
+// However, `Path` layout is considered an implementation detail and must not be relied upon. We
+// want `repr(transparent)` but we don't want it to show up in rustdoc, so we hide it under
+// `cfg(doc)`. This is an ad-hoc implementation of attribute privacy.
 #[cfg_attr(not(doc), repr(transparent))]
 pub struct Path {
     inner: OsStr,