diff --git a/spec/compiler/codegen/c_abi/c_abi_spec.cr b/spec/compiler/codegen/c_abi/c_abi_spec.cr
index 1a772b897ae2..2099c597d770 100644
--- a/spec/compiler/codegen/c_abi/c_abi_spec.cr
+++ b/spec/compiler/codegen/c_abi/c_abi_spec.cr
@@ -84,6 +84,36 @@ describe "Code gen: C ABI" do
       ), &.to_i.should eq(6))
   end
 
+  {% if flag?(:x86_64) && !flag?(:win32) %}
+    pending "passes struct after many other args (for real) (#9519)"
+  {% else %}
+    it "passes struct after many other args (for real)" do
+      test_c(
+        %(
+          struct s {
+            long long x, y;
+          };
+
+          long long foo(long long a, long long b, long long c, long long d, long long e, struct s v) {
+            return a + b + c + d + e + v.x + v.y;
+          }
+        ),
+        %(
+          lib LibFoo
+            struct S
+              x : Int64
+              y : Int64
+            end
+
+            fun foo(a : Int64, b : Int64, c : Int64, d : Int64, e : Int64, v : S) : Int64
+          end
+
+          v = LibFoo::S.new(x: 6, y: 7)
+          LibFoo.foo(1, 2, 3, 4, 5, v)
+        ), &.to_string.should eq("28"))
+    end
+  {% end %}
+
   it "returns struct less than 64 bits (for real)" do
     test_c(
       %(
diff --git a/src/llvm/abi/x86_win64.cr b/src/llvm/abi/x86_win64.cr
index 5a9a07bdb31e..69e9b0823ba9 100644
--- a/src/llvm/abi/x86_win64.cr
+++ b/src/llvm/abi/x86_win64.cr
@@ -12,7 +12,7 @@ class LLVM::ABI::X86_Win64 < LLVM::ABI::X86
         when 2 then ArgType.direct(t, context.int16)
         when 4 then ArgType.direct(t, context.int32)
         when 8 then ArgType.direct(t, context.int64)
-        else        ArgType.indirect(t, LLVM::Attribute::ByVal)
+        else        ArgType.indirect(t, nil)
         end
       else
         non_struct(t, context)