Message-ID: <0befb6fb-d125-95f2-9815-7dbda8086f25@pgmasters.net>
Date: Fri, 25 Mar 2022 09:55:45 -0600
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Subject: Re: ubsan
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To: Andres Freund <andres@anarazel.de>, Tom Lane <tgl@sss.pgh.pa.us>
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From: David Steele <david@pgmasters.net>
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On 3/23/22 16:55, Andres Freund wrote:
> 
> It's particularly impressive that the cost of running with ASAN is *so* much
> lower than valgrind. On my workstation a check-world with
> -fsanitize=alignment,undefined,address takes 3min17s, vs 1min10s or so without
> -fsanitize.  Not something to always use, but certainly better than valgrind.

It also catches things that valgrind does not so that's a bonus.

One thing to note, though. I have noticed that when enabling 
-fsanitize=undefined and/or -fsanitize=address in combination with 
-fprofile-arcs -ftest-coverage there is a loss in reported coverage, at 
least on gcc 9.3. This may not be very obvious unless coverage is 
normally at 100%.

Regards,
-David