diff --git a/tcg/i386/tcg-target.c.inc b/tcg/i386/tcg-target.c.inc
index 5a151fe..5c7c180 100644
--- a/tcg/i386/tcg-target.c.inc
+++ b/tcg/i386/tcg-target.c.inc
@@ -1083,7 +1083,7 @@
 {
     /* This function is only used for passing structs by reference. */
     tcg_debug_assert(imm == (int32_t)imm);
-    tcg_out_modrm_offset(s, OPC_LEA, rd, rs, imm);
+    tcg_out_modrm_offset(s, OPC_LEA | P_REXW, rd, rs, imm);
 }
 
 static inline void tcg_out_pushi(TCGContext *s, tcg_target_long val)