Description:
------------
opcache_invalidate()/zend_accel_invalidate does:

        realpath = accelerator_orig_zend_resolve_path(filename, filename_len);

        if (!realpath) {
                return FAILURE;
        }

accelerator_orig_zend_resolve_path ends up calling php_resolve_path that again
does a tsrm_realpath() that ends up doing lstat() that in the end makes php_resolve_path return NULL and zend_accel_invalidate return FAILURE.

This means it is not possible to invalidate a file that is removed from the filesystem without flushing the entire opcache. This can be problematic in general and for esoteric in particular.

I understand the fact that one might try to resolve symlinks to find real cache key, but there should imho be a way to override this and enable the invalidation.

Another related issue is that opcache_invalidate does not actually free up memory, just marks the cached code as corrupted. How impossible would it
be to implement a opcache_delete call that would do all this?