#include <mongoc.h>

int main() {
	mongoc_client_t *client;
	mongoc_gridfs_t *gridfs;
	bson_error_t error;

	mongoc_init();

	client = mongoc_client_new("mongodb://INVALID-URI");
	BSON_ASSERT(client);
	gridfs = mongoc_client_get_gridfs(client, "test-gridfs", 0, &error);
	BSON_ASSERT(!gridfs);

	mongoc_client_destroy(client);
	mongoc_cleanup();
	return 0;
}

$ ./a.out
Segmentation fault

==10844== Invalid read of size 8
==10844==    at 0x4E4D144: mongoc_cluster_run_command_monitored (mongoc-cluster.c:362)
==10844==    by 0x4E521BA: mongoc_collection_create_index_with_opts (mongoc-collection.c:1325)
==10844==    by 0x4E528AF: mongoc_collection_create_index (mongoc-collection.c:1155)
==10844==    by 0x4E5CCBE: _mongoc_gridfs_ensure_index (mongoc-gridfs.c:66)
==10844==    by 0x4E5CCBE: _mongoc_gridfs_new (mongoc-gridfs.c:133)
==10844==    by 0x400887: main (libmongoc5.c:12)
==10844==  Address 0x8 is not stack'd, malloc'd or (recently) free'd
==10844==
==10844==
==10844== Process terminating with default action of signal 11 (SIGSEGV)
==10844==  Access not within mapped region at address 0x8
==10844==    at 0x4E4D144: mongoc_cluster_run_command_monitored (mongoc-cluster.c:362)
==10844==    by 0x4E521BA: mongoc_collection_create_index_with_opts (mongoc-collection.c:1325)
==10844==    by 0x4E528AF: mongoc_collection_create_index (mongoc-collection.c:1155)
==10844==    by 0x4E5CCBE: _mongoc_gridfs_ensure_index (mongoc-gridfs.c:66)
==10844==    by 0x4E5CCBE: _mongoc_gridfs_new (mongoc-gridfs.c:133)
==10844==    by 0x400887: main (libmongoc5.c:12)