From c85f038307da4435361b2eaaccd187a50ece2c76 Mon Sep 17 00:00:00 2001
From: Vayun Biyani <vayunbiyani@Vayuns-Mac-mini.local>
Date: Thu, 27 Feb 2025 19:32:30 +0530
Subject: [PATCH] switch #[cfg(not(llvm_enzyme))] to cfg!(llvm_enzyme)

---
 compiler/rustc_builtin_macros/src/autodiff.rs | 26 +++----------------
 compiler/rustc_builtin_macros/src/errors.rs   |  4 ---
 2 files changed, 4 insertions(+), 26 deletions(-)

diff --git a/compiler/rustc_builtin_macros/src/autodiff.rs b/compiler/rustc_builtin_macros/src/autodiff.rs
index cad041c7deb..6d9c3575657 100644
--- a/compiler/rustc_builtin_macros/src/autodiff.rs
+++ b/compiler/rustc_builtin_macros/src/autodiff.rs
@@ -3,7 +3,6 @@
 //! configs (autodiff enabled or disabled), so we have to add cfg's to each import.
 //! FIXME(ZuseZ4): Remove this once we have a smarter linter.
 
-#[cfg(llvm_enzyme)]
 mod llvm_enzyme {
     use std::str::FromStr;
     use std::string::String;
@@ -130,6 +129,10 @@ mod llvm_enzyme {
         meta_item: &ast::MetaItem,
         mut item: Annotatable,
     ) -> Vec<Annotatable> {
+        if cfg!(not(llvm_enzyme)) {
+            ecx.sess.dcx().emit_err(errors::AutoDiffSupportNotBuild { span: meta_item.span });
+            return vec![item];
+        }
         let dcx = ecx.sess.dcx();
         // first get the annotable item:
         let (sig, is_impl): (FnSig, bool) = match &item {
@@ -801,25 +804,4 @@ mod llvm_enzyme {
     }
 }
 
-#[cfg(not(llvm_enzyme))]
-mod ad_fallback {
-    use rustc_ast::ast;
-    use rustc_expand::base::{Annotatable, ExtCtxt};
-    use rustc_span::Span;
-
-    use crate::errors;
-    pub(crate) fn expand(
-        ecx: &mut ExtCtxt<'_>,
-        _expand_span: Span,
-        meta_item: &ast::MetaItem,
-        item: Annotatable,
-    ) -> Vec<Annotatable> {
-        ecx.sess.dcx().emit_err(errors::AutoDiffSupportNotBuild { span: meta_item.span });
-        return vec![item];
-    }
-}
-
-#[cfg(not(llvm_enzyme))]
-pub(crate) use ad_fallback::expand;
-#[cfg(llvm_enzyme)]
 pub(crate) use llvm_enzyme::expand;
diff --git a/compiler/rustc_builtin_macros/src/errors.rs b/compiler/rustc_builtin_macros/src/errors.rs
index 6213bd802c7..ab1e0d8ee89 100644
--- a/compiler/rustc_builtin_macros/src/errors.rs
+++ b/compiler/rustc_builtin_macros/src/errors.rs
@@ -144,10 +144,8 @@ pub(crate) struct AllocMustStatics {
     pub(crate) span: Span,
 }
 
-#[cfg(llvm_enzyme)]
 pub(crate) use autodiff::*;
 
-#[cfg(llvm_enzyme)]
 mod autodiff {
     use super::*;
     #[derive(Diagnostic)]
@@ -203,9 +201,7 @@ mod autodiff {
     }
 }
 
-#[cfg(not(llvm_enzyme))]
 pub(crate) use ad_fallback::*;
-#[cfg(not(llvm_enzyme))]
 mod ad_fallback {
     use super::*;
     #[derive(Diagnostic)]