From 2b2b3f8a0e7aa2f15c626c34cce9eb6abf340692 Mon Sep 17 00:00:00 2001
From: Antoni Boucher <bouanto@zoho.com>
Date: Sat, 25 Jul 2026 20:56:04 -0400
Subject: [PATCH 1/3] Fix overaligned argument

---
 src/abi.rs                         | 13 +++++++---
 tests/run/overaligned_byval_arg.rs | 41 ++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+), 3 deletions(-)
 create mode 100644 tests/run/overaligned_byval_arg.rs

diff --git a/src/abi.rs b/src/abi.rs
index 45fc5e3c4f6..2ae60e238ec 100644
--- a/src/abi.rs
+++ b/src/abi.rs
@@ -1,5 +1,5 @@
 #[cfg(feature = "master")]
-use gccjit::FnAttribute;
+use gccjit::{FnAttribute, TypeAttribute};
 use gccjit::{ToLValue, ToRValue, Type};
 #[cfg(feature = "master")]
 use rustc_abi::{ArmCall, CanonAbi, InterruptKind, X86Call};
@@ -187,7 +187,7 @@ impl<'gcc, 'tcx> FnAbiGccExt<'gcc, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                     let ty = cast.gcc_type(cx);
                     apply_attrs(ty, &cast.attrs, argument_tys.len())
                 }
-                PassMode::Indirect { attrs: _, meta_attrs: None, on_stack: true } => {
+                PassMode::Indirect { attrs, meta_attrs: None, on_stack: true } => {
                     let x86_interrupt_first_arg = {
                         #[cfg(feature = "master")]
                         {
@@ -211,7 +211,14 @@ impl<'gcc, 'tcx> FnAbiGccExt<'gcc, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                     } else {
                         // This is a "byval" argument, so we don't apply the `restrict` attribute on it.
                         on_stack_param_indices.insert(argument_tys.len());
-                        arg.layout.gcc_type(cx)
+                        let ty = arg.layout.gcc_type(cx);
+                        #[cfg(feature = "master")]
+                        if let Some(align) = attrs.pointee_align {
+                            ty.add_attribute(TypeAttribute::Aligned(align.bytes() as u8));
+                        }
+                        #[cfg(not(feature = "master"))]
+                        let _ = attrs;
+                        ty
                     }
                 }
                 PassMode::Direct(attrs) => {
diff --git a/tests/run/overaligned_byval_arg.rs b/tests/run/overaligned_byval_arg.rs
new file mode 100644
index 00000000000..e20ec117329
--- /dev/null
+++ b/tests/run/overaligned_byval_arg.rs
@@ -0,0 +1,41 @@
+// Compiler:
+//
+// Run-time:
+//   status: 0
+
+#![feature(no_core)]
+#![no_std]
+#![no_core]
+#![no_main]
+
+extern crate mini_core;
+use mini_core::*;
+
+#[repr(C)]
+struct Big {
+    a: i64,
+    b: i64,
+    c: i64,
+}
+
+#[repr(C, align(64))]
+struct Aligned {
+    x: i32,
+}
+
+#[inline(never)]
+#[no_mangle]
+extern "C" fn check(_b1: Big, a1: Aligned, _b2: Big, a2: Aligned) -> i32 {
+    if (&a1 as *const Aligned as usize) % 64 != 0 {
+        return 1;
+    }
+    if (&a2 as *const Aligned as usize) % 64 != 0 {
+        return 2;
+    }
+    0
+}
+
+#[no_mangle]
+extern "C" fn main(_argc: i32, _argv: *const *const u8) -> i32 {
+    check(Big { a: 1, b: 2, c: 3 }, Aligned { x: 42 }, Big { a: 4, b: 5, c: 6 }, Aligned { x: 43 })
+}

From 34f4a9c5805a5775d56e590b36b0e8ca8436c028 Mon Sep 17 00:00:00 2001
From: Antoni Boucher <bouanto@zoho.com>
Date: Mon, 3 Aug 2026 17:36:18 -0400
Subject: [PATCH 2/3] Add -Wno-psabi to silent a warning

---
 src/gcc_util.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/gcc_util.rs b/src/gcc_util.rs
index d986dc68e67..56314dca5ef 100644
--- a/src/gcc_util.rs
+++ b/src/gcc_util.rs
@@ -193,6 +193,8 @@ pub fn new_context<'gcc>(sess: &Session) -> Context<'gcc> {
     context.add_command_line_option("-fno-strict-aliasing");
     // NOTE: Rust relies on LLVM doing wrapping on overflow.
     context.add_command_line_option("-fwrapv");
+    // NOTE: This is needed to hide a warning caused by the alignment fix on byval arguments.
+    context.add_command_line_option("-Wno-psabi");
 
     if let Some(model) = sess.code_model() {
         use rustc_target::spec::CodeModel;

From db92e5d482fab3149718bf0b903fb90ae00c0518 Mon Sep 17 00:00:00 2001
From: Antoni Boucher <bouanto@zoho.com>
Date: Mon, 3 Aug 2026 17:38:26 -0400
Subject: [PATCH 3/3] Update gccjit dependency

---
 Cargo.lock | 4 ++--
 Cargo.toml | 2 +-
 src/abi.rs | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 060509e51a6..cca0e1e590e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -56,9 +56,9 @@ dependencies = [
 
 [[package]]
 name = "gccjit"
-version = "4.0.0"
+version = "4.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "be5dafc4e649cb4a363e95a5960ef50b0c6f1b8e136ff8eb2e928b40353b5d8b"
+checksum = "859af1dd2815fd0f8ca97f5917a595f18c415692b07e58993a6ad34ff13204d5"
 dependencies = [
  "gccjit_sys",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index 63a20d46b9d..141949e9189 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,7 +20,7 @@ default = ["master"]
 [dependencies]
 object = { version = "0.37.0", default-features = false, features = ["std", "read"] }
 tempfile = "3.20"
-gccjit = { version = "4.0.0", features = ["dlopen"] }
+gccjit = { version = "4.1.0", features = ["dlopen"] }
 #gccjit = { git = "https://github.com/rust-lang/gccjit.rs", branch = "error-dlopen", features = ["dlopen"] }
 
 # Local copy.
diff --git a/src/abi.rs b/src/abi.rs
index 2ae60e238ec..445da17dc39 100644
--- a/src/abi.rs
+++ b/src/abi.rs
@@ -214,7 +214,7 @@ impl<'gcc, 'tcx> FnAbiGccExt<'gcc, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                         let ty = arg.layout.gcc_type(cx);
                         #[cfg(feature = "master")]
                         if let Some(align) = attrs.pointee_align {
-                            ty.add_attribute(TypeAttribute::Aligned(align.bytes() as u8));
+                            ty.add_attribute(TypeAttribute::Aligned(align.bytes() as u32));
                         }
                         #[cfg(not(feature = "master"))]
                         let _ = attrs;