From b3c254d629f715ea6cc225509df14736c2152365 Mon Sep 17 00:00:00 2001
From: kalsprite <jon@lipstate.com>
Date: Mon, 10 Aug 2026 21:48:10 -0700
Subject: [PATCH] i386: pass aggregate arguments by value on the stack

---
 src/llvm_abi.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/llvm_abi.cpp b/src/llvm_abi.cpp
index 528ddca88..3d4af355d 100644
--- a/src/llvm_abi.cpp
+++ b/src/llvm_abi.cpp
@@ -437,7 +437,9 @@ namespace lbAbi386 {
 				if (sz == 0) {
 					args[i] = lb_arg_type_ignore(t);
 				} else {
-					args[i] = lb_arg_type_indirect(t, nullptr);
+					// Aggregates are pushed onto the stack by value, not passed as a pointer
+					// to a caller-owned copy. This is the rule for both i386 targets.
+					args[i] = lb_arg_type_indirect_byval(c, t);
 				}
 			} else {
 				args[i] = non_struct(c, t, false);