From 63bb9519142aca454aff01aad4fc3c1cafc3128c Mon Sep 17 00:00:00 2001
From: "Felix S. Klock II" <pnkfelix@pnkfx.org>
Date: Fri, 26 Aug 2022 12:18:26 -0400
Subject: [PATCH] revert mir inlining policy for beta-1.64 to resolve issue
 #101004.

---
 compiler/rustc_mir_transform/src/inline.rs | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/compiler/rustc_mir_transform/src/inline.rs b/compiler/rustc_mir_transform/src/inline.rs
index 1e46b0a0e8164..76b1522f394f0 100644
--- a/compiler/rustc_mir_transform/src/inline.rs
+++ b/compiler/rustc_mir_transform/src/inline.rs
@@ -9,7 +9,6 @@ use rustc_middle::mir::visit::*;
 use rustc_middle::mir::*;
 use rustc_middle::ty::subst::Subst;
 use rustc_middle::ty::{self, ConstKind, Instance, InstanceDef, ParamEnv, Ty, TyCtxt};
-use rustc_session::config::OptLevel;
 use rustc_span::{hygiene::ExpnKind, ExpnData, LocalExpnId, Span};
 use rustc_target::spec::abi::Abi;
 
@@ -44,15 +43,8 @@ impl<'tcx> MirPass<'tcx> for Inline {
             return enabled;
         }
 
-        match sess.mir_opt_level() {
-            0 | 1 => false,
-            2 => {
-                (sess.opts.optimize == OptLevel::Default
-                    || sess.opts.optimize == OptLevel::Aggressive)
-                    && sess.opts.incremental == None
-            }
-            _ => true,
-        }
+        // rust-lang/rust#101004: reverted to old inlining decision logic
+        sess.mir_opt_level() >= 3
     }
 
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {