7 files changed, 11 insertions, 23 deletions
diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index 3d05fc15b38..6d2ad70af27 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -395,18 +395,14 @@ fn get_pgo_sample_use_path(config: &ModuleConfig) -> Option<CString> {
 }
 
 pub(crate) fn should_use_new_llvm_pass_manager(
-    cgcx: &CodegenContext<LlvmCodegenBackend>,
+    _cgcx: &CodegenContext<LlvmCodegenBackend>,
     config: &ModuleConfig,
 ) -> bool {
-    // The new pass manager is enabled by default for LLVM >= 13.
-    // This matches Clang, which also enables it since Clang 13.
-
-    // FIXME: There are some perf issues with the new pass manager
-    // when targeting s390x, so it is temporarily disabled for that
-    // arch, see https://github.com/rust-lang/rust/issues/89609
+    // The new pass manager is causing significant performance issues such as #91128, and is
+    // therefore disabled in stable versions of rustc by default.
     config
         .new_llvm_pass_manager
-        .unwrap_or_else(|| cgcx.target_arch != "s390x" && llvm_util::get_version() >= (13, 0, 0))
+        .unwrap_or(false)
 }
 
 pub(crate) unsafe fn optimize_with_new_llvm_pass_manager(
diff --git a/compiler/rustc_target/src/spec/aarch64_apple_darwin.rs b/compiler/rustc_target/src/spec/aarch64_apple_darwin.rs
index 3ffc852d650..f01ff02da07 100644
--- a/compiler/rustc_target/src/spec/aarch64_apple_darwin.rs
+++ b/compiler/rustc_target/src/spec/aarch64_apple_darwin.rs
@@ -9,7 +9,6 @@ pub fn target() -> Target {
     base.supported_sanitizers = SanitizerSet::ADDRESS | SanitizerSet::CFI | SanitizerSet::THREAD;
 
     base.pre_link_args.insert(LinkerFlavor::Gcc, vec!["-arch".to_string(), "arm64".to_string()]);
-    base.link_env.extend(super::apple_base::macos_link_env("arm64"));
     base.link_env_remove.extend(super::apple_base::macos_link_env_remove());
 
     // Clang automatically chooses a more specific target based on
diff --git a/compiler/rustc_target/src/spec/apple_base.rs b/compiler/rustc_target/src/spec/apple_base.rs
index ba8f9a8ce11..db6aee59a5d 100644
--- a/compiler/rustc_target/src/spec/apple_base.rs
+++ b/compiler/rustc_target/src/spec/apple_base.rs
@@ -79,18 +79,6 @@ pub fn macos_llvm_target(arch: &str) -> String {
     format!("{}-apple-macosx{}.{}.0", arch, major, minor)
 }
 
-pub fn macos_link_env(arch: &str) -> Vec<(String, String)> {
-    // Use the default deployment target for linking just as with the LLVM target if not
-    // specified via MACOSX_DEPLOYMENT_TARGET, otherwise the system linker would use its
-    // default which varies with Xcode version.
-    if env::var("MACOSX_DEPLOYMENT_TARGET").is_err() {
-        let default = macos_default_deployment_target(arch);
-        vec![("MACOSX_DEPLOYMENT_TARGET".to_string(), format!("{}.{}", default.0, default.1))]
-    } else {
-        vec![]
-    }
-}
-
 pub fn macos_link_env_remove() -> Vec<String> {
     let mut env_remove = Vec::with_capacity(2);
     // Remove the `SDKROOT` environment variable if it's clearly set for the wrong platform, which
diff --git a/compiler/rustc_target/src/spec/i686_apple_darwin.rs b/compiler/rustc_target/src/spec/i686_apple_darwin.rs
index 05217c09aed..f2635f0656d 100644
--- a/compiler/rustc_target/src/spec/i686_apple_darwin.rs
+++ b/compiler/rustc_target/src/spec/i686_apple_darwin.rs
@@ -5,7 +5,6 @@ pub fn target() -> Target {
     base.cpu = "yonah".to_string();
     base.max_atomic_width = Some(64);
     base.pre_link_args.insert(LinkerFlavor::Gcc, vec!["-m32".to_string()]);
-    base.link_env.extend(super::apple_base::macos_link_env("i686"));
     base.link_env_remove.extend(super::apple_base::macos_link_env_remove());
     // don't use probe-stack=inline-asm until rust#83139 and rust#84667 are resolved
     base.stack_probes = StackProbeType::Call;
diff --git a/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs b/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs
index 3e20cb0b272..22fdaabfcb8 100644
--- a/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs
+++ b/compiler/rustc_target/src/spec/x86_64_apple_darwin.rs
@@ -10,7 +10,6 @@ pub fn target() -> Target {
         LinkerFlavor::Gcc,
         vec!["-m64".to_string(), "-arch".to_string(), "x86_64".to_string()],
     );
-    base.link_env.extend(super::apple_base::macos_link_env("x86_64"));
     base.link_env_remove.extend(super::apple_base::macos_link_env_remove());
     // don't use probe-stack=inline-asm until rust#83139 and rust#84667 are resolved
     base.stack_probes = StackProbeType::Call;
diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index b8c66931cbe..4a23206402e 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -20,6 +20,7 @@ use super::{Normalized, NormalizedTy, ProjectionCacheEntry, ProjectionCacheKey};
 use crate::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use crate::infer::{InferCtxt, InferOk, LateBoundRegionConversionTime};
 use crate::traits::error_reporting::InferCtxtExt as _;
+use rustc_data_structures::sso::SsoHashSet;
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_errors::ErrorReported;
 use rustc_hir::def_id::DefId;
@@ -944,9 +945,14 @@ fn opt_normalize_projection_type<'a, 'b, 'tcx>(
                 Normalized { value: projected_ty, obligations: projected_obligations }
             };
 
+            let mut deduped: SsoHashSet<_> = Default::default();
             let mut canonical =
                 SelectionContext::with_query_mode(selcx.infcx(), TraitQueryMode::Canonical);
+
             result.obligations.drain_filter(|projected_obligation| {
+                if !deduped.insert(projected_obligation.clone()) {
+                    return true;
+                }
                 // If any global obligations always apply, considering regions, then we don't
                 // need to include them. The `is_global` check rules out inference variables,
                 // so there's no need for the caller of `opt_normalize_projection_type`
diff --git a/compiler/rustc_type_ir/src/lib.rs b/compiler/rustc_type_ir/src/lib.rs
index 91dbbec782f..f11c93e9339 100644
--- a/compiler/rustc_type_ir/src/lib.rs
+++ b/compiler/rustc_type_ir/src/lib.rs
@@ -559,6 +559,7 @@ impl<CTX> HashStable<CTX> for FloatTy {
 impl<CTX> HashStable<CTX> for InferTy {
     fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
         use InferTy::*;
+        discriminant(self).hash_stable(ctx, hasher);
         match self {
             TyVar(v) => v.as_u32().hash_stable(ctx, hasher),
             IntVar(v) => v.index.hash_stable(ctx, hasher),