Fix memory error during precompilation (#44345)

Fixes #44338

src/dump.c

@@ -272,6 +272,7 @@ static int has_backedge_to_worklist(jl_method_instance_t *mi, htable_t *visited)
  for (i = 0; i < n; i++) {
  jl_method_instance_t *be = (jl_method_instance_t*)jl_array_ptr_ref(mi->backedges, i);
  if (has_backedge_to_worklist(be, visited)) {
+ bp = ptrhash_bp(visited, mi); // re-acquire since rehashing might change the location
  *bp = (void*)((char*)HT_NOTFOUND + 2); // found
  return 1;
  }
@@ -286,10 +287,10 @@ static size_t queue_external_mis(jl_array_t *list)
 {
  size_t i, n = 0;
  htable_t visited;
- htable_new(&visited, 0);
  if (list) {
  assert(jl_is_array(list));
  size_t n0 = jl_array_len(list);
+ htable_new(&visited, n0);
  for (i = 0; i < n0; i++) {
  jl_method_instance_t *mi = (jl_method_instance_t*)jl_array_ptr_ref(list, i);
  assert(jl_is_method_instance(mi));
@@ -2640,7 +2641,7 @@ JL_DLLEXPORT int jl_save_incremental(const char *fname, jl_array_t *worklist)
  arraylist_new(&reinit_list, 0);
  htable_new(&edges_map, 0);
  htable_new(&backref_table, 5000);
- htable_new(&external_mis, 0);
+ htable_new(&external_mis, newly_inferred ? jl_array_len(newly_inferred) : 0);
  ptrhash_put(&backref_table, jl_main_module, (char*)HT_NOTFOUND + 1);
  backref_table_numel = 1;
  jl_idtable_type = jl_base_module ? jl_get_global(jl_base_module, jl_symbol("IdDict")) : NULL;