py: Make sure that static emg-exc-buffer is aligned to size of mp_obj_t.
This buffer is used to allocate objects temporarily, and such objects
require that their underlying memory be correctly aligned for their data
type. Aligning for mp_obj_t should be sufficient for emergency exceptions,
but in general the memory buffer should aligned to the maximum alignment of
the machine (eg on a 32-bit machine with mp_obj_t being 4 bytes, a double
may not be correctly aligned).
This patch fixes a bug for certain nan-boxing builds, where mp_obj_t is 8
bytes and must be aligned to 8 bytes (even though the machine is 32 bit).
diff --git a/py/objexcept.c b/py/objexcept.c
index 1f1009f..dcc7800 100644
--- a/py/objexcept.c
+++ b/py/objexcept.c
@@ -348,7 +348,7 @@
tuple->items[0] = MP_OBJ_FROM_PTR(str);
byte *str_data = (byte *)&str[1];
- uint max_len = MP_STATE_VM(mp_emergency_exception_buf) + mp_emergency_exception_buf_size
+ size_t max_len = (byte*)MP_STATE_VM(mp_emergency_exception_buf) + mp_emergency_exception_buf_size
- str_data;
vstr_t vstr;
@@ -366,14 +366,14 @@
o->args = tuple;
- uint offset = &str_data[str->len] - MP_STATE_VM(mp_emergency_exception_buf);
+ size_t offset = &str_data[str->len] - (byte*)MP_STATE_VM(mp_emergency_exception_buf);
offset += sizeof(void *) - 1;
offset &= ~(sizeof(void *) - 1);
if ((mp_emergency_exception_buf_size - offset) > (sizeof(o->traceback_data[0]) * 3)) {
// We have room to store some traceback.
o->traceback_data = (size_t*)((byte *)MP_STATE_VM(mp_emergency_exception_buf) + offset);
- o->traceback_alloc = (MP_STATE_VM(mp_emergency_exception_buf) + mp_emergency_exception_buf_size - (byte *)o->traceback_data) / sizeof(o->traceback_data[0]);
+ o->traceback_alloc = ((byte*)MP_STATE_VM(mp_emergency_exception_buf) + mp_emergency_exception_buf_size - (byte *)o->traceback_data) / sizeof(o->traceback_data[0]);
o->traceback_len = 0;
}
}