Re: [std-discussion] Is this union aliasing code well-defined?

2017-10-29 Thread Hyman Rosen
In math, once you reach a contradiction, you realize that one of your premises was false. In religion, once you reach a contradiction, you write books of theology to paper over the mess. I guess we know what category type-based alias analysis falls under.

gcc-8-20171029 is now available

2017-10-29 Thread gccadmin
Snapshot gcc-8-20171029 is now available on ftp://gcc.gnu.org/pub/gcc/snapshots/8-20171029/ and on various mirrors, see http://gcc.gnu.org/mirrors.html for details. This snapshot has been generated from the GCC 8 SVN branch with the following options: svn://gcc.gnu.org/svn/gcc/trunk revision

Re: Problems in IPA passes

2017-10-29 Thread Kugan Vivekanandarajah
Hi Jeff, On 28 October 2017 at 18:28, Jeff Law wrote: > > Jan, > > What's the purpose behind calling vrp_meet and > extract_range_from_unary_expr from within the IPA passes? This is used such that when we have an argument to a function and this for which we know the VR and this intern is passed

Re: [std-discussion] Is this union aliasing code well-defined?

2017-10-29 Thread Jeffrey Walton
On Fri, Oct 27, 2017 at 9:00 AM, Yubin Ruan wrote: > ... > On Mon, Sep 25, 2017 at 01:41:55PM -0700, Myriachan wrote: >> This question that "supercat" posted on Stack Overflow ran into an >> interesting problem: >> >> https://stackoverflow.com/questions/46205744/is-this-use-of-unions-strictly-conf

Re: [std-discussion] Is this union aliasing code well-defined?

2017-10-29 Thread Richard Biener
On October 29, 2017 2:46:42 AM GMT+01:00, Yubin Ruan wrote: >On 10/27/2017 04:54 PM, Richard Biener wrote: >> On Fri, Oct 27, 2017 at 3:00 PM, Yubin Ruan >wrote: >>> +Cc gcc-list. >>> >>> Does any gcc developer have any comments? >> >> See PR82224. The code is valid. >> >>> On Mon, Sep 25, 20