diff --git a/compiler/rustc_hir_analysis/src/check/intrinsic.rs b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
index f21aeb4c0b98c..6282499883ba4 100644
--- a/compiler/rustc_hir_analysis/src/check/intrinsic.rs
+++ b/compiler/rustc_hir_analysis/src/check/intrinsic.rs
@@ -26,15 +26,12 @@ fn equate_intrinsic_type<'tcx>(
     n_cts: usize,
     sig: ty::PolyFnSig<'tcx>,
 ) {
-    let (own_counts, span) = match tcx.hir_node_by_def_id(def_id) {
+    let (generics, span) = match tcx.hir_node_by_def_id(def_id) {
         hir::Node::Item(hir::Item { kind: hir::ItemKind::Fn(_, generics, _), .. })
         | hir::Node::ForeignItem(hir::ForeignItem {
             kind: hir::ForeignItemKind::Fn(.., generics, _),
             ..
-        }) => {
-            let own_counts = tcx.generics_of(def_id).own_counts();
-            (own_counts, generics.span)
-        }
+        }) => (tcx.generics_of(def_id), generics.span),
         _ => {
             struct_span_code_err!(tcx.dcx(), span, E0622, "intrinsic must be a function")
                 .with_span_label(span, "expected a function")
@@ -42,6 +39,7 @@ fn equate_intrinsic_type<'tcx>(
             return;
         }
     };
+    let own_counts = generics.own_counts();
 
     let gen_count_ok = |found: usize, expected: usize, descr: &str| -> bool {
         if found != expected {
@@ -57,9 +55,17 @@ fn equate_intrinsic_type<'tcx>(
         }
     };
 
+    // the host effect param should be invisible as it shouldn't matter
+    // whether effects is enabled for the intrinsic provider crate.
+    let consts_count = if generics.host_effect_index.is_some() {
+        own_counts.consts - 1
+    } else {
+        own_counts.consts
+    };
+
     if gen_count_ok(own_counts.lifetimes, n_lts, "lifetime")
         && gen_count_ok(own_counts.types, n_tps, "type")
-        && gen_count_ok(own_counts.consts, n_cts, "const")
+        && gen_count_ok(consts_count, n_cts, "const")
     {
         let _ = check_function_signature(
             tcx,
diff --git a/tests/ui/intrinsics/not-overridden.rs b/tests/ui/intrinsics/not-overridden.rs
index a53071e304d89..93b408331b862 100644
--- a/tests/ui/intrinsics/not-overridden.rs
+++ b/tests/ui/intrinsics/not-overridden.rs
@@ -1,6 +1,6 @@
 //! Check that intrinsics that do not get overridden, but are marked as such,
 //! cause an error instead of silently invoking the body.
-#![feature(rustc_attrs/* , effects*/)] // FIXME(effects)
+#![feature(rustc_attrs)]
 //@ build-fail
 //@ failure-status:101
 //@ normalize-stderr-test ".*note: .*\n\n" -> ""
diff --git a/tests/ui/intrinsics/safe-intrinsic-mismatch.effects.stderr b/tests/ui/intrinsics/safe-intrinsic-mismatch.effects.stderr
new file mode 100644
index 0000000000000..d9a4960feec4d
--- /dev/null
+++ b/tests/ui/intrinsics/safe-intrinsic-mismatch.effects.stderr
@@ -0,0 +1,52 @@
+error: using `#![feature(effects)]` without enabling next trait solver globally
+   |
+   = note: the next trait solver must be enabled globally for the effects feature to work correctly
+   = help: use `-Znext-solver` to enable
+
+error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `size_of`
+  --> $DIR/safe-intrinsic-mismatch.rs:11:5
+   |
+LL |     fn size_of<T>() -> usize;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `size_of`
+  --> $DIR/safe-intrinsic-mismatch.rs:11:5
+   |
+LL |     fn size_of<T>() -> usize;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `assume`
+  --> $DIR/safe-intrinsic-mismatch.rs:16:1
+   |
+LL | const fn assume(_b: bool) {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0308]: intrinsic has wrong type
+  --> $DIR/safe-intrinsic-mismatch.rs:16:16
+   |
+LL | const fn assume(_b: bool) {}
+   |                ^ expected unsafe fn, found safe fn
+   |
+   = note: expected signature `unsafe fn(_)`
+              found signature `fn(_)`
+
+error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `const_deallocate`
+  --> $DIR/safe-intrinsic-mismatch.rs:20:1
+   |
+LL | const fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error[E0308]: intrinsic has wrong type
+  --> $DIR/safe-intrinsic-mismatch.rs:20:26
+   |
+LL | const fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
+   |                          ^ expected unsafe fn, found safe fn
+   |
+   = note: expected signature `unsafe fn(_, _, _)`
+              found signature `fn(_, _, _)`
+
+error: aborting due to 7 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/intrinsics/safe-intrinsic-mismatch.rs b/tests/ui/intrinsics/safe-intrinsic-mismatch.rs
index c116ba7a62eeb..af563e996c1df 100644
--- a/tests/ui/intrinsics/safe-intrinsic-mismatch.rs
+++ b/tests/ui/intrinsics/safe-intrinsic-mismatch.rs
@@ -1,6 +1,11 @@
+//@ revisions: stock effects
 #![feature(intrinsics)]
 #![feature(rustc_attrs)]
-// FIXME(effects) do this with revisions #![feature(effects)]
+// as effects insert a const generic param to const intrinsics,
+// check here that it doesn't report a const param mismatch either
+// enabling or disabling effects.
+#![cfg_attr(effects, feature(effects))]
+#![allow(incomplete_features)]
 
 extern "rust-intrinsic" {
     fn size_of<T>() -> usize; //~ ERROR intrinsic safety mismatch
diff --git a/tests/ui/intrinsics/safe-intrinsic-mismatch.stderr b/tests/ui/intrinsics/safe-intrinsic-mismatch.stock.stderr
similarity index 86%
rename from tests/ui/intrinsics/safe-intrinsic-mismatch.stderr
rename to tests/ui/intrinsics/safe-intrinsic-mismatch.stock.stderr
index 7f37e0f821118..6864c0f36ded0 100644
--- a/tests/ui/intrinsics/safe-intrinsic-mismatch.stderr
+++ b/tests/ui/intrinsics/safe-intrinsic-mismatch.stock.stderr
@@ -1,11 +1,11 @@
 error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `size_of`
-  --> $DIR/safe-intrinsic-mismatch.rs:6:5
+  --> $DIR/safe-intrinsic-mismatch.rs:11:5
    |
 LL |     fn size_of<T>() -> usize;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `size_of`
-  --> $DIR/safe-intrinsic-mismatch.rs:6:5
+  --> $DIR/safe-intrinsic-mismatch.rs:11:5
    |
 LL |     fn size_of<T>() -> usize;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^
@@ -13,13 +13,13 @@ LL |     fn size_of<T>() -> usize;
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `assume`
-  --> $DIR/safe-intrinsic-mismatch.rs:11:1
+  --> $DIR/safe-intrinsic-mismatch.rs:16:1
    |
 LL | const fn assume(_b: bool) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error[E0308]: intrinsic has wrong type
-  --> $DIR/safe-intrinsic-mismatch.rs:11:16
+  --> $DIR/safe-intrinsic-mismatch.rs:16:16
    |
 LL | const fn assume(_b: bool) {}
    |                ^ expected unsafe fn, found safe fn
@@ -28,13 +28,13 @@ LL | const fn assume(_b: bool) {}
               found signature `fn(_)`
 
 error: intrinsic safety mismatch between list of intrinsics within the compiler and core library intrinsics for intrinsic `const_deallocate`
-  --> $DIR/safe-intrinsic-mismatch.rs:15:1
+  --> $DIR/safe-intrinsic-mismatch.rs:20:1
    |
 LL | const fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error[E0308]: intrinsic has wrong type
-  --> $DIR/safe-intrinsic-mismatch.rs:15:26
+  --> $DIR/safe-intrinsic-mismatch.rs:20:26
    |
 LL | const fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
    |                          ^ expected unsafe fn, found safe fn
diff --git a/tests/ui/rfcs/rfc-2632-const-trait-impl/effects/minicore.rs b/tests/ui/rfcs/rfc-2632-const-trait-impl/effects/minicore.rs
index af88a73b4d692..63c353c7d6627 100644
--- a/tests/ui/rfcs/rfc-2632-const-trait-impl/effects/minicore.rs
+++ b/tests/ui/rfcs/rfc-2632-const-trait-impl/effects/minicore.rs
@@ -1,12 +1,16 @@
 //@ known-bug: #110395
+//@ failure-status: 101
+//@ normalize-stderr-test ".*note: .*\n\n" -> ""
+//@ normalize-stderr-test "thread 'rustc' panicked.*:\n.*\n" -> ""
+//@ rustc-env:RUST_BACKTRACE=0
 // FIXME(effects) check-pass
-// FIXME(effects) fix intrinsics const parameter counting
+//@ compile-flags: -Znext-solver
 
 #![crate_type = "lib"]
 #![feature(no_core, lang_items, unboxed_closures, auto_traits, intrinsics, rustc_attrs, staged_api)]
-#![feature(fundamental)]
+#![feature(fundamental, marker_trait_attr)]
 #![feature(const_trait_impl, effects, const_mut_refs)]
-#![allow(internal_features)]
+#![allow(internal_features, incomplete_features)]
 #![no_std]
 #![no_core]
 #![stable(feature = "minicore", since = "1.0.0")]
@@ -532,3 +536,35 @@ fn test_const_eval_select() {
 
     const_eval_select((), const_fn, rt_fn);
 }
+
+mod effects {
+    use super::Sized;
+
+    #[lang = "EffectsNoRuntime"]
+    pub struct NoRuntime;
+    #[lang = "EffectsMaybe"]
+    pub struct Maybe;
+    #[lang = "EffectsRuntime"]
+    pub struct Runtime;
+
+    #[lang = "EffectsCompat"]
+    pub trait Compat<#[rustc_runtime] const RUNTIME: bool> {}
+
+    impl Compat<false> for NoRuntime {}
+    impl Compat<true> for Runtime {}
+    impl<#[rustc_runtime] const RUNTIME: bool> Compat<RUNTIME> for Maybe {}
+
+    #[lang = "EffectsTyCompat"]
+    #[marker]
+    pub trait TyCompat<T: ?Sized> {}
+
+    impl<T: ?Sized> TyCompat<T> for T {}
+    impl<T: ?Sized> TyCompat<T> for Maybe {}
+    impl<T: ?Sized> TyCompat<Maybe> for T {}
+
+    #[lang = "EffectsIntersection"]
+    pub trait Intersection {
+        #[lang = "EffectsIntersectionOutput"]
+        type Output: ?Sized;
+    }
+}
diff --git a/tests/ui/rfcs/rfc-2632-const-trait-impl/effects/minicore.stderr b/tests/ui/rfcs/rfc-2632-const-trait-impl/effects/minicore.stderr
index 1963332b856de..823ab69df9cb5 100644
--- a/tests/ui/rfcs/rfc-2632-const-trait-impl/effects/minicore.stderr
+++ b/tests/ui/rfcs/rfc-2632-const-trait-impl/effects/minicore.stderr
@@ -1,17 +1,13 @@
-warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
-  --> $DIR/minicore.rs:8:30
-   |
-LL | #![feature(const_trait_impl, effects, const_mut_refs)]
-   |                              ^^^^^^^
-   |
-   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
-   = note: `#[warn(incomplete_features)]` on by default
+error: the compiler unexpectedly panicked. this is a bug.
 
-error: requires `EffectsCompat` lang_item
-  --> $DIR/minicore.rs:455:9
-   |
-LL | impl<T: Clone> Clone for RefCell<T> {
-   |         ^^^^^
+query stack during panic:
+#0 [check_well_formed] checking that `<impl at $DIR/minicore.rs:459:1: 459:36>` is well-formed
+#1 [check_mod_type_wf] checking that types are well-formed in top-level module
+end of query stack
 
-error: aborting due to 1 previous error; 1 warning emitted
+error: the compiler unexpectedly panicked. this is a bug.
 
+query stack during panic:
+#0 [check_well_formed] checking that `drop` is well-formed
+#1 [check_mod_type_wf] checking that types are well-formed in top-level module
+end of query stack