djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Clear the buffer byte between ATB and FTB

Browse Source 
This ensures it has a known start state. An unknown state risks it
looking like a tail block similar to the problem fixed by #5245.

Fixes #5305
This commit is contained in:
Scott Shawcroft 2021-09-14 16:24:37 -07:00
parent dfba2ee26e
commit e544909b5b
No known key found for this signature in database
GPG Key ID: 0DFD512649C052DA
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
py/gc.c
View File

@ -150,8 +150,10 @@ void gc_init(void *start, void *end) {
assert(MP_STATE_MEM(gc_pool_start) >= MP_STATE_MEM(gc_finaliser_table_start) + gc_finaliser_table_byte_len);
#endif
// clear ATBs
memset(MP_STATE_MEM(gc_alloc_table_start), 0, MP_STATE_MEM(gc_alloc_table_byte_len));
// Clear ATBs plus one more byte. The extra byte might be read when we read the final ATB and
// then try to count its tail. Clearing the byte ensures it is 0 and ends the chain. Without an
// FTB, it'll just clear the pool byte early.
memset(MP_STATE_MEM(gc_alloc_table_start), 0, MP_STATE_MEM(gc_alloc_table_byte_len) + 1);
#if MICROPY_ENABLE_FINALISER
// clear FTBs