Auto merge of #130348 - Zalathar:rollup-5d0b7a9, r=Zalathar

Rollup of 4 pull requests

Successful merges:

 - #130053 (fix doc comments for Peekable::next_if(_eq))
 - #130267 (small_data_threshold.rs: Adapt to LLVM head changes)
 - #130311 ((fix) conflicting negative impl marker)
 - #130334 (Fix `SDKROOT` ignore on macOS)

r? `@ghost`
`@rustbot` modify labels: rollup

3 files changed, 14 insertions, 2 deletions

diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs
index 40eb35deea5..8b855bd0dd5 100644
--- a/compiler/rustc_codegen_ssa/src/back/link.rs
+++ b/compiler/rustc_codegen_ssa/src/back/link.rs
@@ -3044,7 +3044,7 @@ fn get_apple_sdk_root(sdk_name: &str) -> Result<String, errors::AppleSdkRootErro
             "iphonesimulator"
                 if sdkroot.contains("iPhoneOS.platform") || sdkroot.contains("MacOSX.platform") => {
             }
-            "macosx10.15"
+            "macosx"
                 if sdkroot.contains("iPhoneOS.platform")
                     || sdkroot.contains("iPhoneSimulator.platform") => {}
             "watchos"
diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/mod.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/mod.rs
index 9aa6d1f3d46..752ef729113 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/traits/mod.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/traits/mod.rs
@@ -344,7 +344,8 @@ pub(crate) fn to_pretty_impl_header(tcx: TyCtxt<'_>, impl_def_id: DefId) -> Opti
 
     write!(
         w,
-        " {} for {}",
+        " {}{} for {}",
+        tcx.impl_polarity(impl_def_id).as_str(),
         trait_ref.print_only_trait_path(),
         tcx.type_of(impl_def_id).instantiate_identity()
     )
diff --git a/compiler/rustc_type_ir/src/predicate.rs b/compiler/rustc_type_ir/src/predicate.rs
index b30346ffc53..e4bf1e1379c 100644
--- a/compiler/rustc_type_ir/src/predicate.rs
+++ b/compiler/rustc_type_ir/src/predicate.rs
@@ -196,6 +196,17 @@ impl fmt::Display for ImplPolarity {
     }
 }
 
+impl ImplPolarity {
+    /// The polarity marker in front of the impl trait ref if applicable.
+    pub fn as_str(self) -> &'static str {
+        match self {
+            Self::Positive => "",
+            Self::Negative => "!",
+            Self::Reservation => "",
+        }
+    }
+}
+
 /// Polarity for a trait predicate. May either be negative or positive.
 /// Distinguished from [`ImplPolarity`] since we never compute goals with
 /// "reservation" level.