Remove the omit_gdb_pretty_printer_section attribute

Disabling loading of pretty printers in the debugger itself is more
reliable. Before this commit the .gdb_debug_scripts section couldn't be
included in dylibs or rlibs as otherwise there is no way to disable the
section anymore without recompiling the entire standard library.

compiler/rustc_feature/src/builtin_attrs.rs

@@ -1257,11 +1257,6 @@ pub static BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         TEST, rustc_dummy, Normal, template!(Word /* doesn't matter*/),
         DuplicatesOk, EncodeCrossCrate::No
     ),
-    gated!(
-        omit_gdb_pretty_printer_section, Normal, template!(Word),
-        WarnFollowing, EncodeCrossCrate::No,
-        "the `#[omit_gdb_pretty_printer_section]` attribute is just used for the Rust test suite",
-    ),
     rustc_attr!(
         TEST, pattern_complexity_limit, CrateLevel, template!(NameValueStr: "N"),
         ErrorFollowing, EncodeCrossCrate::No,

compiler/rustc_feature/src/removed.rs

@@ -199,6 +199,8 @@ declare_features! (
     /// Renamed to `dyn_compatible_for_dispatch`.
     (removed, object_safe_for_dispatch, "1.83.0", Some(43561),
      Some("renamed to `dyn_compatible_for_dispatch`"), 131511),
+    /// Allows using `#[omit_gdb_pretty_printer_section]`.
+    (removed, omit_gdb_pretty_printer_section, "CURRENT_RUSTC_VERSION", None, None, 144738),
     /// Allows using `#[on_unimplemented(..)]` on traits.
     /// (Moved to `rustc_attrs`.)
     (removed, on_unimplemented, "1.40.0", None, None, 65794),

compiler/rustc_feature/src/unstable.rs

@@ -225,8 +225,6 @@ declare_features! (
     (unstable, multiple_supertrait_upcastable, "1.69.0", None),
     /// Allow negative trait bounds. This is an internal-only feature for testing the trait solver!
     (internal, negative_bounds, "1.71.0", None),
-    /// Allows using `#[omit_gdb_pretty_printer_section]`.
-    (internal, omit_gdb_pretty_printer_section, "1.5.0", None),
     /// Set the maximum pattern complexity allowed (not limited by default).
     (internal, pattern_complexity_limit, "1.78.0", None),
     /// Allows using pattern types.