From: Tom Tromey <tom@tromey.com>
To: Pedro Alves <palves@redhat.com>
Cc: Tom Tromey <tom@tromey.com>, gdb-patches@sourceware.org
Subject: Re: [PATCH 0/9] Add UBSan to the build
Date: Wed, 29 Aug 2018 00:45:00 -0000 [thread overview]
Message-ID: <87tvnevw5i.fsf@tromey.com> (raw)
In-Reply-To: <152ef6ac-cd48-72be-6fae-9397bca2c8b8@redhat.com> (Pedro Alves's message of "Tue, 28 Aug 2018 20:03:19 +0100")
>>>>> "Pedro" == Pedro Alves <palves@redhat.com> writes:
Pedro> I think this is a good idea. On enabling this by default on devel
Pedro> builds, do you have a sense of CPU/memory overhead this introduces?
I have no idea about the CPU. It doesn't seem notably slower to me but
I am not sure I would really notice.
I don't think -fsanitize=undefined has notable memory overhead. I
believe it just introduces checks at spots where undefined behavior
might be possible.
It does increase the size of gdb:
size before:
text data bss dec hex filename
23070184 2372034 323664 25765882 18927fa gdb
size after:
text data bss dec hex filename
26879230 9135154 324688 36339072 22a7d80 gdb
I think this isn't so important because it's only for development mode
and because it can be turned off if need be.
Though, let's not oversell it -- UB sanitization didn't catch anything
very important. Address sanitizer, on the other hand, did; and if I can
fix that last bug I would like to give -fsanitize=address the same
treatment as was done here.
Tom
next prev parent reply other threads:[~2018-08-29 0:45 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-27 14:57 Tom Tromey
2018-08-27 14:57 ` [PATCH 5/9] Avoid undefined behavior in parse_number Tom Tromey
2018-08-27 14:57 ` [PATCH 1/9] Do not pass NULL to memcpy Tom Tromey
2018-08-27 19:12 ` Simon Marchi
2018-08-28 22:40 ` Tom Tromey
2018-08-27 14:57 ` [PATCH 2/9] Use unsigned as base type for some enums Tom Tromey
2018-08-27 19:22 ` Simon Marchi
2018-08-27 20:22 ` Tom Tromey
2018-08-27 21:26 ` Simon Marchi
2018-08-28 18:54 ` Pedro Alves
2018-08-28 22:42 ` Tom Tromey
2018-08-29 0:01 ` Tom Tromey
2018-08-27 14:57 ` [PATCH 3/9] Avoid undefined behavior in extract_integer Tom Tromey
2018-08-28 18:39 ` Pedro Alves
2018-08-29 0:11 ` Tom Tromey
2018-08-27 14:57 ` [PATCH 6/9] Avoid undefined behavior in read_signed_leb128 Tom Tromey
2018-08-27 14:57 ` [PATCH 7/9] Avoid undefined behavior in ada_operator_length Tom Tromey
2018-08-27 14:59 ` [PATCH 8/9] Avoid undefined behavior in expression dumping Tom Tromey
2018-08-28 18:49 ` Pedro Alves
2018-08-29 0:27 ` Tom Tromey
2018-08-27 14:59 ` [PATCH 4/9] Avoid undefined behavior in read_subrange_type Tom Tromey
2018-08-27 14:59 ` [PATCH 9/9] Add --enable-ubsan Tom Tromey
2018-08-28 19:03 ` [PATCH 0/9] Add UBSan to the build Pedro Alves
2018-08-29 0:45 ` Tom Tromey [this message]
2018-08-30 18:41 ` Pedro Alves
2018-08-30 18:56 ` Tom Tromey
2018-08-30 19:06 ` Pedro Alves
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