From c17a818b18f914f08e645d7be47c1848dd64e437 Mon Sep 17 00:00:00 2001
From: b1yd <2156864690@qq.com>
Date: Tue, 16 Jun 2026 13:12:27 +0800
Subject: [PATCH] fix

---
 compiler/rustc_hir_analysis/src/check/wfcheck.rs | 12 ++++++++++--
 compiler/rustc_hir_analysis/src/diagnostics.rs   |  9 +++++++++
 compiler/rustc_resolve/src/ident.rs              |  5 ++++-
 tests/ui/resolve/allow-self-in-const-generics.rs | 16 ++++++++++++++++
 .../resolve/allow-self-in-const-generics.stderr  |  9 +++++++++
 5 files changed, 48 insertions(+), 3 deletions(-)
 create mode 100644 tests/ui/resolve/allow-self-in-const-generics.rs
 create mode 100644 tests/ui/resolve/allow-self-in-const-generics.stderr

diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
index bf8593eb61882..cdfec8d20b91a 100644
--- a/compiler/rustc_hir_analysis/src/check/wfcheck.rs
+++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
@@ -45,7 +45,7 @@ use super::compare_eii::{compare_eii_function_types, compare_eii_statics};
 use crate::autoderef::Autoderef;
 use crate::constrained_generic_params::{Parameter, identify_constrained_generic_params};
 use crate::diagnostics;
-use crate::diagnostics::InvalidReceiverTyHint;
+use crate::diagnostics::{InvalidReceiverTyHint, ParamInTyOfConstParam};
 
 pub(super) struct WfCheckingCtxt<'a, 'tcx> {
     pub(super) ocx: ObligationCtxt<'a, 'tcx, FulfillmentError<'tcx>>,
@@ -855,7 +855,15 @@ fn check_param_wf(tcx: TyCtxt<'_>, param: &ty::GenericParamDef) -> Result<(), Er
             let ty = tcx.type_of(param.def_id).instantiate_identity().skip_norm_wip();
             let span = tcx.def_span(param.def_id);
             let def_id = param.def_id.expect_local();
-
+            if !tcx.features().generic_const_parameter_types() && ty.has_param() {
+                let hir::GenericParamKind::Const { ty: &hir::Ty { span, .. }, .. } =
+                    tcx.hir_node_by_def_id(def_id).expect_generic_param().kind
+                else {
+                    bug!()
+                };
+                let err = tcx.dcx().create_err(ParamInTyOfConstParam { span, ty }).emit();
+                return Err(err);
+            }
             if tcx.features().const_param_ty_unchecked() {
                 enter_wf_checking_ctxt(tcx, tcx.local_parent(def_id), |wfcx| {
                     wfcx.register_wf_obligation(span, None, ty.into());
diff --git a/compiler/rustc_hir_analysis/src/diagnostics.rs b/compiler/rustc_hir_analysis/src/diagnostics.rs
index 1bfc495071284..ed16241dd418f 100644
--- a/compiler/rustc_hir_analysis/src/diagnostics.rs
+++ b/compiler/rustc_hir_analysis/src/diagnostics.rs
@@ -2000,3 +2000,12 @@ impl<G: EmissionGuarantee> Diagnostic<'_, G> for UncoveredTyParam<'_> {
         diag
     }
 }
+
+#[derive(Diagnostic)]
+#[diag("the type of const parameters must not depend on other generic parameters", code = E0770)]
+pub(crate) struct ParamInTyOfConstParam<'tcx> {
+    #[primary_span]
+    #[label("the type `{$ty}` must not depend on other generic parameter")]
+    pub(crate) span: Span,
+    pub(crate) ty: Ty<'tcx>,
+}
diff --git a/compiler/rustc_resolve/src/ident.rs b/compiler/rustc_resolve/src/ident.rs
index 9d08e8b98cb31..9bcc929462542 100644
--- a/compiler/rustc_resolve/src/ident.rs
+++ b/compiler/rustc_resolve/src/ident.rs
@@ -1584,7 +1584,10 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
                         }
 
                         RibKind::ConstParamTy => {
-                            if !self.features.generic_const_parameter_types() {
+                            // We check whether Self depends on generics parameters during HIR analysis
+                            if !self.features.generic_const_parameter_types()
+                                && !matches!(res, Res::SelfTyAlias { .. })
+                            {
                                 if let Some(span) = finalize {
                                     self.report_error(
                                         span,
diff --git a/tests/ui/resolve/allow-self-in-const-generics.rs b/tests/ui/resolve/allow-self-in-const-generics.rs
new file mode 100644
index 0000000000000..8dcde2a66fff7
--- /dev/null
+++ b/tests/ui/resolve/allow-self-in-const-generics.rs
@@ -0,0 +1,16 @@
+// Allow Self in const generics when Self doesn't depends on generics
+trait MyTrait {
+    fn foo<const N: i32>();
+}
+
+impl MyTrait for i32 {
+    fn foo<const N: Self>() {}
+}
+impl<T> Wrap<T> {
+    fn f<const N: Self>() {}
+    //~^ ERROR the type of const parameters must not depend on other generic parameters
+
+}
+
+struct Wrap<T>(T);
+fn main(){}
diff --git a/tests/ui/resolve/allow-self-in-const-generics.stderr b/tests/ui/resolve/allow-self-in-const-generics.stderr
new file mode 100644
index 0000000000000..52a70f739bc8c
--- /dev/null
+++ b/tests/ui/resolve/allow-self-in-const-generics.stderr
@@ -0,0 +1,9 @@
+error[E0770]: the type of const parameters must not depend on other generic parameters
+  --> $DIR/allow-self-in-const-generics.rs:10:19
+   |
+LL |     fn f<const N: Self>() {}
+   |                   ^^^^ the type `Wrap<T>` must not depend on other generic parameter
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0770`.