This is the mail archive of the
mailing list for the GCC project.
Re: [RFC] UBSan unsafely uses VRP
- From: Yury Gribov <y dot gribov at samsung dot com>
- To: Jakub Jelinek <jakub at redhat dot com>, Marat Zakirov <m dot zakirov at samsung dot com>
- Cc: GCC Mailing List <gcc at gcc dot gnu dot org>, Richard Biener <richard dot guenther at gmail dot com>
- Date: Wed, 12 Nov 2014 11:42:39 +0300
- Subject: Re: [RFC] UBSan unsafely uses VRP
- Authentication-results: sourceware.org; auth=none
- References: <5462170F dot 5040102 at samsung dot com> <20141111141521 dot GE5026 at tucnak dot redhat dot com>
On 11/11/2014 05:15 PM, Jakub Jelinek wrote:
There are also some unsafe code in functions
which uses get_range_info to reduce checks number. As seen before vrp usage
for sanitizers may decrease quality of error detection.
Using VRP is completely intentional there, we don't want to generate too
slow code if you decide you want to optimize your code (for -O0 VRP isn't
performed of course).
On the other hand detection quality is probably more important than
important regardless of optimization level. When I use a checker, I
don't want it to miss bugs due to overly aggressive optimization.
I wish we had some test to check that sanitizer optimizations are indeed