Add NaCl SDK release note about LLVM 3.6 and debug metadata changes.

BUG=none

Review URL: https://codereview.chromium.org/1051653004

Cr-Commit-Position: refs/heads/master@{#323291}

4 files changed, 21 insertions, 1 deletions

diff --git a/native_client_sdk/doc_generated/devguide/devcycle/debugging.html b/native_client_sdk/doc_generated/devguide/devcycle/debugging.html
index adc9710..300dffc 100644
--- a/native_client_sdk/doc_generated/devguide/devcycle/debugging.html
+++ b/native_client_sdk/doc_generated/devguide/devcycle/debugging.html
@@ -195,7 +195,7 @@ that matches the SDK version. Developers who may have left the
 <code>--enable-nacl-debug</code> flag turned on may end up loading the debug
 copy of your application (which may or may not work, depending on
 their version of Chrome).</p>
-<h4 id="debugging-pnacl-pexes-with-older-pepper-toolchains">Debugging PNaCl pexes (with older Pepper toolchains)</h4>
+<h4 id="debugging-pnacl-pexes-with-older-pepper-toolchains"><span id="debugging-pexes-via-nexes"></span>Debugging PNaCl pexes (with older Pepper toolchains)</h4>
 <p>If you want to use GDB to debug a program that is compiled with the PNaCl
 toolchain, you must convert the <code>pexe</code> file to a <code>nexe</code>.  (You can skip
 this step if you are using the GCC toolchain, or if you are using
diff --git a/native_client_sdk/doc_generated/sdk/release-notes.html b/native_client_sdk/doc_generated/sdk/release-notes.html
index 7ef7f66..20836b5 100644
--- a/native_client_sdk/doc_generated/sdk/release-notes.html
+++ b/native_client_sdk/doc_generated/sdk/release-notes.html
@@ -12,6 +12,15 @@ generated by default. The in-browser Chrome 42 translator supports them, the
 SDK can therefore generate them.</li>
 <li>Fix a <a class="reference external" href="https://code.google.com/p/chromium/issues/detail?id=460432">code generation bug on ARM</a> when dealing with 16-bit load/store and
 <code>bswap</code> which led to a NaCl validation failure.</li>
+<li>PNaCl is now based on LLVM 3.6. If you are using GDB to debug PNaCl
+<a class="reference internal" href="/native-client/devguide/devcycle/debugging.html#debugging-pnacl-pexes"><em>BC files with debug metadata in the browser</em></a>,
+remember that debug info from SDK version <code>X</code> is only compatible with the
+PNaCl translator in chrome version <code>X</code>. The bitcode debug metadata format
+changed from LLVM 3.5 to 3.6. If you need to debug an app built with SDK
+version <code>X</code> running in Chrome version <code>Y</code> (with <code>X != Y</code>), it is still
+possible to do so. Simply translate the pexe to a nexe using the
+<a class="reference internal" href="/native-client/devguide/devcycle/debugging.html#debugging-pexes-via-nexes"><em>offline pnacl-translate tool from SDK version X</em></a> instead of using the translator in the
+browser (version <code>Y</code>).</li>
 </ul>
 <h2 id="chrome-pepper-42-20-february-2015">Chrome/Pepper 42 (20 February 2015)</h2>
 <h3 id="sdk">SDK</h3>
diff --git a/native_client_sdk/src/doc/devguide/devcycle/debugging.rst b/native_client_sdk/src/doc/devguide/devcycle/debugging.rst
index 35cba5a..0e2503e 100644
--- a/native_client_sdk/src/doc/devguide/devcycle/debugging.rst
+++ b/native_client_sdk/src/doc/devguide/devcycle/debugging.rst
@@ -231,6 +231,7 @@ that matches the SDK version. Developers who may have left the
 copy of your application (which may or may not work, depending on
 their version of Chrome).
 
+.. _debugging_pexes_via_nexes:
 
 Debugging PNaCl pexes (with older Pepper toolchains)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/native_client_sdk/src/doc/sdk/release-notes.rst b/native_client_sdk/src/doc/sdk/release-notes.rst
index 8fbf326..e88569a 100644
--- a/native_client_sdk/src/doc/sdk/release-notes.rst
+++ b/native_client_sdk/src/doc/sdk/release-notes.rst
@@ -19,6 +19,16 @@ PNaCl
   SDK can therefore generate them.
 * Fix a `code generation bug on ARM`_ when dealing with 16-bit load/store and
   ``bswap`` which led to a NaCl validation failure.
+* PNaCl is now based on LLVM 3.6. If you are using GDB to debug PNaCl
+  :ref:`BC files with debug metadata in the browser<debugging_pnacl_pexes>`,
+  remember that debug info from SDK version ``X`` is only compatible with the
+  PNaCl translator in chrome version ``X``. The bitcode debug metadata format
+  changed from LLVM 3.5 to 3.6. If you need to debug an app built with SDK
+  version ``X`` running in Chrome version ``Y`` (with ``X != Y``), it is still
+  possible to do so. Simply translate the pexe to a nexe using the
+  :ref:`offline pnacl-translate tool from SDK version X
+  <debugging_pexes_via_nexes>` instead of using the translator in the
+  browser (version ``Y``).
 
 .. _`code generation bug on ARM`: https://code.google.com/p/chromium/issues/detail?id=460432