Introduced in PR 9208 this assert at or near to src/include/btree_inline.h:1562 uses volatile in an apparent attempt to ensure ref->addr is explicitly loaded from memory.

WT_ASSERT(session, (volatile void *)ref->addr != NULL);

However this cast indicates the memory addr is pointing to is volatile, rather than pointer. The value of the pointer is then tested which is not volatile.

I believe the pointer needs to be cast a to a volatile pointer and then dereferenced.

WT_ASSERT(session, *(void * volatile *)&ref->addr != NULL);

I think (tentatively) this is required 6.7.3 of the C11/C17 specifications.