From 94fbb2178ae5960894aaae199233b0d3ac020d79 Mon Sep 17 00:00:00 2001
From: Folkert de Vries <folkert@folkertdev.nl>
Date: Sun, 27 Jul 2025 21:21:07 +0200
Subject: implement `va_arg` for arm in rustc itself

---
 compiler/rustc_codegen_llvm/src/va_arg.rs | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

(limited to 'compiler/rustc_codegen_llvm/src/va_arg.rs')

diff --git a/compiler/rustc_codegen_llvm/src/va_arg.rs b/compiler/rustc_codegen_llvm/src/va_arg.rs
index 7eb5d302058..ab08125217f 100644
--- a/compiler/rustc_codegen_llvm/src/va_arg.rs
+++ b/compiler/rustc_codegen_llvm/src/va_arg.rs
@@ -908,6 +908,21 @@ pub(super) fn emit_va_arg<'ll, 'tcx>(
             )
         }
         "aarch64" => emit_aapcs_va_arg(bx, addr, target_ty),
+        "arm" => {
+            // Types wider than 16 bytes are not currently supported. Clang has special logic for
+            // such types, but `VaArgSafe` is not implemented for any type that is this large.
+            assert!(bx.cx.size_of(target_ty).bytes() <= 16);
+
+            emit_ptr_va_arg(
+                bx,
+                addr,
+                target_ty,
+                PassMode::Direct,
+                SlotSize::Bytes4,
+                AllowHigherAlign::Yes,
+                ForceRightAdjust::No,
+            )
+        }
         "s390x" => emit_s390x_va_arg(bx, addr, target_ty),
         "powerpc" => emit_powerpc_va_arg(bx, addr, target_ty),
         "powerpc64" | "powerpc64le" => emit_ptr_va_arg(
-- 
cgit 1.4.1-3-g733a5