From f74cf39a7434c73424b9e5fddaf78996bd2b06c1 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Wed, 15 Dec 2021 16:53:35 +0100
Subject: [PATCH] Fix crash when struct argument size is not a multiple of the
 pointer size

Fixes #1200
---
 src/abi/pass_mode.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/abi/pass_mode.rs b/src/abi/pass_mode.rs
index c01ed249904..9f0bd31e95f 100644
--- a/src/abi/pass_mode.rs
+++ b/src/abi/pass_mode.rs
@@ -117,7 +117,9 @@ impl<'tcx> ArgAbiExt<'tcx> for ArgAbi<'tcx, Ty<'tcx>> {
             PassMode::Cast(cast) => cast_target_to_abi_params(cast),
             PassMode::Indirect { attrs, extra_attrs: None, on_stack } => {
                 if on_stack {
-                    let size = u32::try_from(self.layout.size.bytes()).unwrap();
+                    // Abi requires aligning struct size to pointer size
+                    let size = self.layout.size.align_to(tcx.data_layout.pointer_align.abi);
+                    let size = u32::try_from(size.bytes()).unwrap();
                     smallvec![apply_arg_attrs_to_abi_param(
                         AbiParam::special(pointer_ty(tcx), ArgumentPurpose::StructArgument(size),),
                         attrs