doc: fix remaining TODOs in Go 1.6 release notes

Fixes #14300.

Change-Id: Idb6a300fe0e06fb8966cf06b55f9b252752a69a6
Reviewed-on: https://go-review.googlesource.com/19459Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

doc/asm.html

@@ -621,6 +621,15 @@ These modes accept only 1, 2, 4, and 8 as scale factors.
 
 </ul>
 
+<p>
+When using the compiler and assembler's
+<code>-dynlink</code> or <code>-shared</code> modes,
+any load or store of a fixed memory location such as a global variable
+must be assumed to overwrite <code>CX</code>.
+Therefore, to be safe for use with these modes,
+assembly sources should typically avoid CX except between memory references.
+</p>
+
 <h3 id="amd64">64-bit Intel 386 (a.k.a. amd64)</h3>
 
 <p>

doc/go1.6.html

@@ -17,6 +17,7 @@ ul li { margin: 0.5em 0; }
 <i>NOTE: This is a DRAFT of the Go 1.6 release notes, prepared for the Go 1.6 beta.
 Go 1.6 has NOT yet been released.
 By our regular schedule, it is expected some time in February 2016.
+<!-- NOTE: WHEN REMOVING THIS COMMENT FIX THE TITLE AT THE TOP OF THE FILE TOO! -->
 </i>
 </p>
 
@@ -70,9 +71,12 @@ On NaCl, Go 1.5 required SDK version pepper-41.
 Go 1.6 adds support for later SDK versions.
 </p>
 
-<pre>
-TODO: CX no longer available on 386 assembly? (https://golang.org/cl/16386)
-</pre>
+<p>
+On 32-bit x86 systems using the <code>-dynlink</code> or <code>-shared</code> compilation modes,
+the register CX is now overwritten by certain memory references and should
+be avoided in hand-written assembly.
+See the <a href="/doc/asm#x86">assembly documentation</a> for details.
+</p>
 
 <h2 id="tools">Tools</h2>
 
@@ -632,7 +636,6 @@ In previous releases, the argument to <code>*</code> was required to have type <
 Also in the <a href="/pkg/fmt/"><code>fmt</code></a> package,
 <a href="/pkg/fmt/#Scanf"><code>Scanf</code></a> can now scan hexadecimal strings using %X, as an alias for %x.
 Both formats accept any mix of upper- and lower-case hexadecimal.
-<a href="https://golang.org/issues/13585">TODO: Keep?</a>
 </li>
 
 <li>
@@ -717,9 +720,6 @@ Second, DNS lookup functions such as
 <a href="/pkg/net/#LookupAddr"><code>LookupAddr</code></a>
 now return rooted domain names (with a trailing dot)
 on Plan 9 and Windows, to match the behavior of Go on Unix systems.
-TODO: Third, lookups satisfied from /etc/hosts now add a trailing dot as well,
-so that looking up 127.0.0.1 typically now returns &ldquo;localhost.&rdquo; not &ldquo;localhost&rdquo;.
-This is arguably a mistake but is not yet fixed. See https://golang.org/issue/13564.
 </li>
 
 <li>