From f45f8262078bde0435560a1e17fb749d0f46dc30 Mon Sep 17 00:00:00 2001
From: Luqman Aden <me@luqman.ca>
Date: Mon, 16 May 2022 21:46:20 -0700
Subject: [PATCH] Update MIR passes that assumed inline can never unwind.

---
 compiler/rustc_mir_transform/src/abort_unwinding_calls.rs | 7 +++++++
 compiler/rustc_mir_transform/src/generator.rs             | 4 ++--
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs b/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs
index ade6555f4d2..11980382ffd 100644
--- a/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs
+++ b/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs
@@ -1,4 +1,5 @@
 use crate::MirPass;
+use rustc_ast::InlineAsmOptions;
 use rustc_hir::def::DefKind;
 use rustc_middle::mir::*;
 use rustc_middle::ty::layout;
@@ -85,6 +86,12 @@ fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
                 TerminatorKind::Assert { .. } | TerminatorKind::FalseUnwind { .. } => {
                     layout::fn_can_unwind(tcx, None, Abi::Rust)
                 }
+                TerminatorKind::InlineAsm { options, .. } => {
+                    options.contains(InlineAsmOptions::MAY_UNWIND)
+                }
+                _ if terminator.unwind().is_some() => {
+                    span_bug!(span, "unexpected terminator that may unwind {:?}", terminator)
+                }
                 _ => continue,
             };
 
diff --git a/compiler/rustc_mir_transform/src/generator.rs b/compiler/rustc_mir_transform/src/generator.rs
index b7dec57b757..9e7bf5c7929 100644
--- a/compiler/rustc_mir_transform/src/generator.rs
+++ b/compiler/rustc_mir_transform/src/generator.rs
@@ -1042,8 +1042,7 @@ fn can_unwind<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'tcx>) -> bool {
             | TerminatorKind::Unreachable
             | TerminatorKind::GeneratorDrop
             | TerminatorKind::FalseEdge { .. }
-            | TerminatorKind::FalseUnwind { .. }
-            | TerminatorKind::InlineAsm { .. } => {}
+            | TerminatorKind::FalseUnwind { .. } => {}
 
             // Resume will *continue* unwinding, but if there's no other unwinding terminator it
             // will never be reached.
@@ -1057,6 +1056,7 @@ fn can_unwind<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'tcx>) -> bool {
             TerminatorKind::Drop { .. }
             | TerminatorKind::DropAndReplace { .. }
             | TerminatorKind::Call { .. }
+            | TerminatorKind::InlineAsm { .. }
             | TerminatorKind::Assert { .. } => return true,
         }
     }