Message-ID: <aa2ef679-a651-48b2-8db8-9fbcefbd0853@gmail.com>
Date: Wed, 5 Nov 2025 10:00:01 +0200
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: ubsan
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>, pgsql-hackers@postgresql.org
References: <20220323173537.ll7klrglnp4gn2um@alap3.anarazel.de>
 <2771659.1648058090@sss.pgh.pa.us>
 <20220930011755.dg7am3kjzebpxxne@awork3.anarazel.de>
 <20221121231503.rb7yim6xlfrs3wu2@alap3.anarazel.de>
 <dbf77bf7-6e54-ed8a-c4ae-d196eeb664ce@gmail.com>
 <709338.1762306456@sss.pgh.pa.us>
Content-Language: en-US
From: Alexander Lakhin <exclusion@gmail.com>
In-Reply-To: <709338.1762306456@sss.pgh.pa.us>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Archived-At: 
 <https://www.postgresql.org/message-id/aa2ef679-a651-48b2-8db8-9fbcefbd0853%40gmail.com>
Precedence: bulk

Hello Tom,

05.11.2025 03:34, Tom Lane wrote:
> Alexander Lakhin <exclusion@gmail.com> writes:
>> I've just discovered that that function __ubsan_default_options() is
>> incompatible with -fsanitize=hwaddress:
>> $ tmp_install/usr/local/pgsql/bin/postgres
>> Segmentation fault
> Hi Alexander, I wonder if you can still reproduce this problem,
> and if so whether the patch proposed at [1] fixes it.
>
> 			regards, tom lane
>
> [1] https://www.postgresql.org/message-id/707073.1762305575%40sss.pgh.pa.us

I don't have that device handy, but I've tried -fsanitize=hwaddress on two
ARM servers available, and despite other issues I've encountered, I could
reproduce the problem with __ubsan_default_options() on current master:
Program received signal SIGSEGV, Segmentation fault.
0x0000aaaaaed06e1c in __ubsan_default_options () at main.c:507
507     if (!reached_main)
(gdb) bt
#0  0x0000aaaaaed06e1c in __ubsan_default_options () at main.c:507
#1  0x0000aaaaac489d84 in __hwasan_init ()
#2  0x0000fffff7fc25c8 in _dl_init (main_map=0xfffff7fff380, argc=1, argv=0xfffffffff3f8, env=0xfffffffff408) at 
./elf/dl-init.c:106
#3  0x0000fffff7fd8d38 in _start () at ../sysdeps/aarch64/dl-start.S:46

The proposed patch really eliminates it. Thank you for recalling this!

Best regards,
Alexander