Porting to GCC 12

From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1314) id 650663858D35; Wed, 29 Sep 2021 08:53:00 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 650663858D35 To: gcc-cvs-wwwdocs@gcc.gnu.org Subject: gcc-wwwdocs branch master updated. 4405fd98dff55185e7ca3ca43e8ab108985d2bb2 X-Git-Refname: refs/heads/master X-Git-Reftype: branch X-Git-Oldrev: 158eee20b5257e9b3d0654f5fe10e60d1741bebe X-Git-Newrev: 4405fd98dff55185e7ca3ca43e8ab108985d2bb2 Message-Id: <20210929085300.650663858D35@sourceware.org> Date: Wed, 29 Sep 2021 08:53:00 +0000 (GMT) From: Andrew Pinski X-BeenThere: gcc-cvs-wwwdocs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs-wwwdocs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Sep 2021 08:53:00 -0000 This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "gcc-wwwdocs". The branch, master has been updated via 4405fd98dff55185e7ca3ca43e8ab108985d2bb2 (commit) from 158eee20b5257e9b3d0654f5fe10e60d1741bebe (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- commit 4405fd98dff55185e7ca3ca43e8ab108985d2bb2 Author: Andrew Pinski Date: Wed Sep 29 00:30:57 2021 +0000 [www] Add note about computed gotos to changes and porting guide Even though there is not many computed gotos in the wild and even less that would use an integer type, it would still be a good idea to add this new error message to both changes and the porting to guide. OK? diff --git a/htdocs/gcc-12/changes.html b/htdocs/gcc-12/changes.html index 1f156a9a..31307107 100644 --- a/htdocs/gcc-12/changes.html +++ b/htdocs/gcc-12/changes.html @@ -17,11 +17,9 @@

This page is a "brief" summary of some of the huge number of improvements in GCC 12. -

Note: GCC 12 has not been released yet, so this document is @@ -30,6 +28,10 @@ a work-in-progress.

Caveats

+ C: + Computed gotos require a pointer type now. +
C++: Two non-standard std::pair constructors have been deprecated. diff --git a/htdocs/gcc-12/porting_to.html b/htdocs/gcc-12/porting_to.html new file mode 100644 index 00000000..9154d7b3 --- /dev/null +++ b/htdocs/gcc-12/porting_to.html @@ -0,0 +1,66 @@ + + + + + +Porting to GCC 12 + + + + +
Porting to GCC 12
+ +
+The GCC 12 release series differs from previous GCC releases in +a number of ways. Some of these are a result +of bug fixing, and some old behaviors have been intentionally changed +to support new standards, or relaxed in standards-conforming ways to +facilitate compilation or run-time performance. +
+ +
+Some of these changes are user visible and can cause grief when +porting to GCC 12. This document is an effort to identify common issues +and provide solutions. Let us know if you have suggestions for improvements! +
+ + + +
C language issues
+ +
Computed goto now require a pointer type
+ +
+In GCC 12, computed gotos require a pointer type. +An example which was accepted before:
+
```
+  void f(void)
+  {
+    goto *10;
+  }
+
```
+is no longer accepted and you need to add a cast to it like: + +
```
+  void f(void)
+  {
+    goto *(void*)10;
+  }
+
```
+ + + + + + + + + ----------------------------------------------------------------------- Summary of changes: htdocs/gcc-12/changes.html | 6 ++-- htdocs/gcc-12/porting_to.html | 66 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 70 insertions(+), 2 deletions(-) create mode 100644 htdocs/gcc-12/porting_to.html hooks/post-receive -- gcc-wwwdocs

Caveats

Porting to GCC 12

C language issues

Computed goto now require a pointer type