diff --git a/lang/s7/files/patch-s7.c b/lang/s7/files/patch-s7.c
new file mode 100644
index 000000000000..5e178948fb04
--- /dev/null
+++ b/lang/s7/files/patch-s7.c
@@ -0,0 +1,29 @@
+--- s7.c.orig	2026-07-07 00:00:00 UTC
++++ s7.c
+@@ -888,6 +888,18 @@
+   union {
+     s7_uint u64_type;             /* type info */
+     s7_int s64_type;
++#if (defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__))
++    struct {
++      uint8_t type_pad[7];
++      uint8_t type_field;
++    };
++    struct {
++      uint16_t high_bits;
++      uint16_t opt_bits;
++      uint16_t mid_bits;
++      uint16_t low_bits;
++    } bits;
++#else
+     uint8_t type_field;
+     struct {
+       uint16_t low_bits;          /* 8 bits for type (type_field above, pair?/string? etc, 6 bits in use), 8 flag bits */
+@@ -895,6 +907,7 @@
+       uint16_t opt_bits;          /* 16 bits for opcode (eval choice), 10 in use) */
+       uint16_t high_bits;         /* 16 more flag bits */
+     } bits;
++#endif
+   } tf;
+   union {
+