[wwwdocs,ARM,AArch64] Document ABI changes and fixes

Message ID 69bdec9a-69c2-d5c5-dff0-c5c0df43bdb3@arm.com
State New
Headers show

Commit Message

Richard Earnshaw (lists) May 2, 2017, 4:32 p.m.
This patch adds some release notes for the gcc ABI changes affecting ARM
and AArch64.

Does this sound reasonable?

R.

Comments

Jakub Jelinek May 2, 2017, 8:34 p.m. | #1
On Tue, May 02, 2017 at 05:32:21PM +0100, Richard Earnshaw (lists) wrote:
> This patch adds some release notes for the gcc ABI changes affecting ARM

> and AArch64.

> 

> Does this sound reasonable?


LGTM.

	Jakub
Gerald Pfeifer May 3, 2017, 10:40 p.m. | #2
On Tue, 2 May 2017, Richard Earnshaw (lists) wrote:
> This patch adds some release notes for the gcc ABI changes affecting ARM 

> and AArch64.


This looks fine, thank you.

The one thing you may want to look into is where it says "code 
where class objects are passed by value to functions" which feels
a bit odd.  Perhaps "...passed to functions by value" or just omit
"to functions" given how common of a phrase "passing by value" is?

Gerald

Patch hide | download patch | download mbox

Index: changes.html
===================================================================
RCS file: /cvs/gcc/wwwdocs/htdocs/gcc-7/changes.html,v
retrieving revision 1.80
diff -u -r1.80 changes.html
--- changes.html	1 May 2017 17:51:14 -0000	1.80
+++ changes.html	2 May 2017 15:34:33 -0000
@@ -38,6 +38,17 @@ 
   </li>
 
   <li>The Cilk+ extensions to the C and C++ languages have been deprecated.</li>
+  <li>On ARM targets (<code>arm*-*-*</code>),
+      <a href="https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77728">a
+      bug</a> introduced in GCC 5 that affects conformance to the
+      procedure call standard (AAPCS) has been fixed.  The bug affects
+      some C++ code where class objects are passed by value to
+      functions and could result in incorrect or inconsistent code
+      being generated.  This is an ABI change.  If the
+      option <code>-Wpsabi</code> is enabled (on by default) the
+      compiler will emit a diagnostic note for code that might be
+      affected.
+  </li>
 </ul>
 
 <!-- .................................................................. -->
@@ -822,6 +833,11 @@ 
 <h3 id="aarch64">AArch64</h3>
    <ul>
      <li>
+       GCC has been updated to the latest revision of the procedure
+       call standard (AAPCS64) to provide support for paramater
+       passing when data types have been over-aligned.
+     </li>
+     <li>
        The ARMv8.3-A architecture is now supported.  It can be used by
        specifying the <code>-march=armv8.3-a</code> option.
      </li>