---
title: "Go, Backwards Compatibility, and GODEBUG"
layout: article
---

<!--
This document is kept in the Go repo, not x/website,
because it documents the full list of known GODEBUG settings,
which are tied to a specific release.
-->

## Introduction {#intro}

Go's emphasis on backwards compatibility is one of its key strengths.
There are, however, times when we cannot maintain complete compatibility.

 * #copyOf(Multimap)}) instead preserves key-grouped order by inserting entries for an existing key
 * immediately after the last entry having that key.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible

				ErrDetail: fmt.Sprintf("unable to update peer targets on local: %v", err),
			}, nil
		}
	}

	// set partial error message if remote site updates failed for few cases
	if len(errs) > 0 {
		successMsg = fmt.Sprintf("%s\n- partially failed for few remote sites as they could be down/unreachable at the moment", successMsg)
	}
	result := madmin.ReplicateEditStatus{
		Success: true,

 * <i>if and only if</i> {@code a.equals(b)}. If this advice is not followed, the resulting
 * collection will not correctly obey its specification.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *
 * @author Louis Wasserman
 * @since 12.0
 */
@GwtIncompatible // hasn't been tested yet

    Object key = new Object();
    assertNotNull(cache.getUnchecked(key));

    CacheTesting.simulateValueReclamation(cache, key);

    // this blocks if computation can't deal with partially-collected values
    assertNotNull(cache.getUnchecked(key));
    assertEquals(1, cache.size());
    assertEquals(2, countingLoader.getCount());

    CacheTesting.simulateValueReclamation(cache, key);

	} else {
		w, err = s.openFile(filePath, flags, skipParent)
	}
	if err != nil {
		return err
	}

	_, err = w.Write(b)
	if err != nil {
		w.Truncate(0) // to indicate that we did partial write.
		w.Close()
		return err
	}

	// Dealing with error returns from close() - 'man 2 close'
	//
	// A careful programmer will check the return value of close(), since it is quite possible that

 * are <i>lazy</i>, which means that their iterators only advance the backing iteration when
 * absolutely necessary.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#iterables">{@code
 * Iterables}</a>.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible

makes it unnecessary.

  3. Protecting Users' Legal Rights From Anti-Circumvention Law.

  No covered work shall be deemed part of an effective technological
measure under any applicable law fulfilling obligations under article
11 of the WIPO copyright treaty adopted on 20 December 1996, or
similar laws prohibiting or restricting circumvention of such
measures.

  When you convey a covered work, you waive any legal power to forbid

 *  Fix: Digits may be used in a URL scheme.
 *  Fix: Improve connection timeout recovery.
 *  Fix: Recover from `getsockname` crashes impacting Android releases prior to
    4.2.2.
 *  Fix: Drop partial support for HTTP/1.0. Previously OkHttp would send
    `HTTP/1.0` on connections after seeing a response with `HTTP/1.0`. The fixed
    behavior is consistent with Firefox and Chrome.
 *  Fix: Allow a body in `OPTIONS` requests.

 * {@link Comparable} class specification. Otherwise, the resulting multiset will violate the {@link
 * java.util.Collection} contract, which is specified in terms of {@link Object#equals}.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#multiset">{@code Multiset}</a>.
 *
 * @author Louis Wasserman
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible