Auto merge of #83908 - Flying-Toast:master, r=davidtwco

Add enum_intrinsics_non_enums lint

There is a clippy lint to prevent calling [`mem::discriminant`](https://doc.rust-lang.org/std/mem/fn.discriminant.html) with a non-enum type. I think the lint is worthy of being included in rustc, given that `discriminant::<T>()` where `T` is a non-enum has an unspecified return value, and there are no valid use cases where you'd actually want this.

I've also made the lint check [variant_count](https://doc.rust-lang.org/core/mem/fn.variant_count.html) (#73662).

closes #83899

1 files changed, 3 insertions, 0 deletions

diff --git a/compiler/rustc_lint/src/lib.rs b/compiler/rustc_lint/src/lib.rs
index 17eb0054584..6f684a0fe51 100644
--- a/compiler/rustc_lint/src/lib.rs
+++ b/compiler/rustc_lint/src/lib.rs
@@ -47,6 +47,7 @@ mod array_into_iter;
 pub mod builtin;
 mod context;
 mod early;
+mod enum_intrinsics_non_enums;
 mod internal;
 mod late;
 mod levels;
@@ -76,6 +77,7 @@ use rustc_span::Span;
 
 use array_into_iter::ArrayIntoIter;
 use builtin::*;
+use enum_intrinsics_non_enums::EnumIntrinsicsNonEnums;
 use internal::*;
 use methods::*;
 use non_ascii_idents::*;
@@ -168,6 +170,7 @@ macro_rules! late_lint_passes {
                 TemporaryCStringAsPtr: TemporaryCStringAsPtr,
                 NonPanicFmt: NonPanicFmt,
                 NoopMethodCall: NoopMethodCall,
+                EnumIntrinsicsNonEnums: EnumIntrinsicsNonEnums,
                 InvalidAtomicOrdering: InvalidAtomicOrdering,
                 NamedAsmLabels: NamedAsmLabels,
             ]