Re: pgcrypto: remove useless px_memset() and BF_ASM - Mailing list pgsql-hackers

From Peter Eisentraut
Subject Re: pgcrypto: remove useless px_memset() and BF_ASM
Date
Msg-id 71e4b3c9-571f-49d3-881d-0f40b0ca55eb@eisentraut.org
Whole thread
In response to Re: pgcrypto: remove useless px_memset() and BF_ASM  (Daniel Gustafsson <daniel@yesql.se>)
Responses Re: pgcrypto: remove useless px_memset() and BF_ASM
List pgsql-hackers
On 09.04.26 21:07, Daniel Gustafsson wrote:
>> On 9 Apr 2026, at 13:51, Dagfinn Ilmari Mannsåker <ilmari@ilmari.org> wrote:
> 
>> In the thread about centralised architecture detection, I noticed that
>> the BF_ASM macro in crypt-blowfish.c has never been defined to anything
>> but 0, and the _BF_body_r() function it would call has never existed, so
>> that can be got rid of.
> 
> Agreed.  I didn't do enough archaeology to figure out what upstream has/had or
> why it was removed, but it's been dead for 25 odd years so it's about time to
> remove.
> 
>> While investigating at that, I also noticed that px_memset(), which has
>> the comment /* memset that must not be optimized away */, is only ever
>> called with zero for the value, which could be better written with
>> explicit_bzero() now that we have that.
> 
> One could imagine various tricks for rewriting px_memset to explicit_bzero in
> order to reduce the churn, but since this code is very rarely backpatched into
> it's not a big problem IMHO.

I have committed these two patches.  One of them was also discussed in 
another thread, but I have co-credited this thread.




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