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Message-ID: <477fa513-6bf0-456d-8d24-1e22a19df671@technowledgy.de>
Date: Wed, 20 Mar 2024 10:39:20 +0100
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
From: Wolfgang Walther <walther@technowledgy.de>
Subject: Re: Regression tests fail with musl libc because libpq.so can't be
 loaded
Content-Language: en-US
To: Thomas Munro <thomas.munro@gmail.com>, peter@eisentraut.org
Cc: Bruce Momjian <bruce@momjian.us>, Christophe Pettus <xof@thebuild.com>,
 Andrew Dunstan <andrew@dunslane.net>,
 PostgreSQL Bugs <pgsql-bugs@lists.postgresql.org>,
 Tom Lane <tgl@sss.pgh.pa.us>
References: <855a1b16-0dc0-42b2-8f90-79eb49cf2893@technowledgy.de>
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Thomas Munro:
> On Wed, Mar 20, 2024 at 3:03 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> +1 for stopping only at one of those two names.
> 
> Here's one like that for Wolfgang to test on musl.

Works fine.

Peter Eisentraut:
> We could turn it around and do
> 
> #if defined(__linux__)
> #if defined(__GLIBC__) || defined(__UCLIBC__ )
> #define PS_USE_CLOBBER_ARGV
> #else
> #define PS_USE_NONE
> #endif
> #endif

This works as well.

I also put together a PoC of what was mentioned in musl's mailing list: 
Instead of clobbering environ at all, exec yourself again with padded 
argv0. This works, too. Attached.

Best,

Wolfgang
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