diff --git a/py/mpconfig.h b/py/mpconfig.h
index 4bfbde2bcc..195eb5981a 100644
--- a/py/mpconfig.h
+++ b/py/mpconfig.h
@@ -1424,6 +1424,12 @@ typedef double mp_float_t;
 #define MICROPY_PY_STRUCT (MICROPY_CONFIG_ROM_LEVEL_AT_LEAST_CORE_FEATURES)
 #endif
 
+// CIRCUITPY-CHANGE
+// Whether to provide non-standard typecodes in "struct" module
+#ifndef MICROPY_NONSTANDARD_TYPECODES
+#define MICROPY_NONSTANDARD_TYPECODES (1)
+#endif
+
 // Whether to provide "sys" module
 #ifndef MICROPY_PY_SYS
 #define MICROPY_PY_SYS (MICROPY_CONFIG_ROM_LEVEL_AT_LEAST_CORE_FEATURES)
diff --git a/py/objexcept.c b/py/objexcept.c
index ba3166a2ab..0f7dd06e3d 100644
--- a/py/objexcept.c
+++ b/py/objexcept.c
@@ -344,6 +344,7 @@ void mp_obj_exception_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
         } else if (attr == MP_QSTR_strerror) {
             if (self->args->len > 1) {
                 dest[0] = self->args->items[1];
+            #if MICROPY_PY_ERRNO
             } else if (self->args->len > 0) {
                 char decompressed[50];
                 const char *msg = mp_common_errno_to_str(self->args->items[0], decompressed, sizeof(decompressed));
@@ -352,6 +353,7 @@ void mp_obj_exception_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
                 } else {
                     dest[0] = mp_const_none;
                 }
+            #endif
             } else {
                 dest[0] = mp_const_none;
             }