UBSAN is reporting the following problem, even when I compile without BSON_EXTRA_ALIGN:
gridfs> fs <- gridfs(url = "mongodb+srv://readwrite:test@cluster0-84vdt.mongodb.net/test") mongoc/mongoc-client.c:279:11: runtime error: load of misaligned address 0x7ffd21a4a479 for type 'short int', which requires 2 byte alignment 0x7ffd21a4a479: note: pointer points here 00 00 00 00 69 89 1a 63 6c 75 73 74 65 72 30 2d 73 68 61 72 64 2d 30 30 2d 30 31 2d 38 34 76 64 ^