diff --git a/src/abi/mod.rs b/src/abi/mod.rs
index 2c038f22ca99b..5d775b9b53229 100644
--- a/src/abi/mod.rs
+++ b/src/abi/mod.rs
@@ -39,7 +39,7 @@ fn clif_sig_from_fn_abi<'tcx>(
 pub(crate) fn conv_to_call_conv(sess: &Session, c: Conv, default_call_conv: CallConv) -> CallConv {
     match c {
         Conv::Rust | Conv::C => default_call_conv,
-        Conv::RustCold => CallConv::Cold,
+        Conv::Cold | Conv::PreserveMost | Conv::PreserveAll => CallConv::Cold,
         Conv::X86_64SysV => CallConv::SystemV,
         Conv::X86_64Win64 => CallConv::WindowsFastcall,
 
@@ -48,7 +48,9 @@ pub(crate) fn conv_to_call_conv(sess: &Session, c: Conv, default_call_conv: Call
             default_call_conv
         }
 
-        Conv::X86Intr => sess.fatal("x86-interrupt call conv not yet implemented"),
+        Conv::X86Intr | Conv::RiscvInterrupt { .. } => {
+            sess.fatal(format!("interrupt call conv {c:?} not yet implemented"))
+        }
 
         Conv::ArmAapcs => sess.fatal("aapcs call conv not yet implemented"),
         Conv::CCmseNonSecureCall => {
diff --git a/src/base.rs b/src/base.rs
index 522dd7189fe63..9159bc3698755 100644
--- a/src/base.rs
+++ b/src/base.rs
@@ -474,10 +474,10 @@ fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) {
                     *destination,
                 );
             }
-            TerminatorKind::Terminate => {
-                codegen_panic_cannot_unwind(fx, source_info);
+            TerminatorKind::UnwindTerminate(reason) => {
+                codegen_unwind_terminate(fx, source_info, *reason);
             }
-            TerminatorKind::Resume => {
+            TerminatorKind::UnwindResume => {
                 // FIXME implement unwinding
                 fx.bcx.ins().trap(TrapCode::UnreachableCodeReached);
             }
@@ -971,13 +971,14 @@ pub(crate) fn codegen_panic_nounwind<'tcx>(
     codegen_panic_inner(fx, rustc_hir::LangItem::PanicNounwind, &args, source_info.span);
 }
 
-pub(crate) fn codegen_panic_cannot_unwind<'tcx>(
+pub(crate) fn codegen_unwind_terminate<'tcx>(
     fx: &mut FunctionCx<'_, '_, 'tcx>,
     source_info: mir::SourceInfo,
+    reason: UnwindTerminateReason,
 ) {
     let args = [];
 
-    codegen_panic_inner(fx, rustc_hir::LangItem::PanicCannotUnwind, &args, source_info.span);
+    codegen_panic_inner(fx, reason.lang_item(), &args, source_info.span);
 }
 
 fn codegen_panic_inner<'tcx>(
diff --git a/src/common.rs b/src/common.rs
index 3081dcfa2b7a3..ec2da39398b2d 100644
--- a/src/common.rs
+++ b/src/common.rs
@@ -480,7 +480,7 @@ impl<'tcx> LayoutOfHelpers<'tcx> for RevealAllLayoutCx<'tcx> {
         if let LayoutError::SizeOverflow(_) | LayoutError::ReferencesError(_) = err {
             self.0.sess.span_fatal(span, err.to_string())
         } else {
-            span_bug!(span, "failed to get layout for `{}`: {}", ty, err)
+            self.0.sess.span_fatal(span, format!("failed to get layout for `{}`: {}", ty, err))
         }
     }
 }
diff --git a/src/constant.rs b/src/constant.rs
index c31535742957c..a934b0767f174 100644
--- a/src/constant.rs
+++ b/src/constant.rs
@@ -550,8 +550,8 @@ pub(crate) fn mir_operand_get_const_val<'tcx>(
                 match &bb_data.terminator().kind {
                     TerminatorKind::Goto { .. }
                     | TerminatorKind::SwitchInt { .. }
-                    | TerminatorKind::Resume
-                    | TerminatorKind::Terminate
+                    | TerminatorKind::UnwindResume
+                    | TerminatorKind::UnwindTerminate(_)
                     | TerminatorKind::Return
                     | TerminatorKind::Unreachable
                     | TerminatorKind::Drop { .. }
diff --git a/src/driver/jit.rs b/src/driver/jit.rs
index 3ea3884214805..1c606494f383e 100644
--- a/src/driver/jit.rs
+++ b/src/driver/jit.rs
@@ -98,7 +98,7 @@ pub(crate) fn run_jit(tcx: TyCtxt<'_>, backend_config: BackendConfig) -> ! {
         tcx.sess.fatal("JIT mode doesn't work with `cargo check`");
     }
 
-    if !tcx.sess.crate_types().contains(&rustc_session::config::CrateType::Executable) {
+    if !tcx.crate_types().contains(&rustc_session::config::CrateType::Executable) {
         tcx.sess.fatal("can't jit non-executable crate");
     }
 
diff --git a/src/unsize.rs b/src/unsize.rs
index 6aeba13f63949..c6133f2b35cf0 100644
--- a/src/unsize.rs
+++ b/src/unsize.rs
@@ -88,7 +88,8 @@ fn unsize_ptr<'tcx>(
                 let src_f = src_layout.field(fx, i);
                 assert_eq!(src_layout.fields.offset(i).bytes(), 0);
                 assert_eq!(dst_layout.fields.offset(i).bytes(), 0);
-                if src_f.is_zst() {
+                if src_f.is_1zst() {
+                    // We are looking for the one non-1-ZST field; this is not it.
                     continue;
                 }
                 assert_eq!(src_layout.size, src_f.size);
@@ -151,6 +152,7 @@ pub(crate) fn coerce_unsized_into<'tcx>(
                 let dst_f = dst.place_field(fx, FieldIdx::new(i));
 
                 if dst_f.layout().is_zst() {
+                    // No data here, nothing to copy/coerce.
                     continue;
                 }
 
diff --git a/src/vtable.rs b/src/vtable.rs
index b309695c190f8..7598c6eee03ff 100644
--- a/src/vtable.rs
+++ b/src/vtable.rs
@@ -51,8 +51,8 @@ pub(crate) fn get_ptr_and_method_ref<'tcx>(
             'descend_newtypes: while !arg.layout().ty.is_unsafe_ptr() && !arg.layout().ty.is_ref() {
                 for i in 0..arg.layout().fields.count() {
                     let field = arg.value_field(fx, FieldIdx::new(i));
-                    if !field.layout().is_zst() {
-                        // we found the one non-zero-sized field that is allowed
+                    if !field.layout().is_1zst() {
+                        // we found the one non-1-ZST field that is allowed
                         // now find *its* non-zero-sized field, or stop if it's a
                         // pointer
                         arg = field;