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	Fri, 12 May 2023 17:13:10 +0200
From: Florian Weimer <fw@deneb.enyo.de>
To: Lukasz Stelmach via Libc-alpha <libc-alpha@sourceware.org>
Cc: Lukasz Stelmach <l.stelmach@samsung.com>,  schwab@suse.de,
  maskray@google.com,  fweimer@redhat.com,  palmer@dabbelt.com,
  adhemerval.zanella@linaro.org,  joseph@codesourcery.com,
  binutils@sourceware.org,  Marek Pikula <m.pikula@partner.samsung.com>,
  Marek Szyprowski <m.szyprowski@samsung.com>,  Karol Lewandowski
 <k.lewandowsk@samsung.com>
Subject: Re: global pointer gets overwritten with dlopen(3) on RISC-V
References: <CGME20230512142114eucas1p112d969a89ad2480a0c10a532bd6d8440@eucas1p1.samsung.com>
	<oypijda5y97hre.fsf%l.stelmach@samsung.com>
Date: Fri, 12 May 2023 17:13:10 +0200
In-Reply-To: <oypijda5y97hre.fsf%l.stelmach@samsung.com> (Lukasz Stelmach via
	Libc-alpha's message of "Fri, 12 May 2023 16:21:09 +0200")
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* Lukasz Stelmach via Libc-alpha:

> We've got a program (the testee) written in C that we test with another
> one (a testing harness, the tester) written in C++ with gtest. So far,
> so good. To make the testing and inspection of the internal state of the
> testee easier the tester does not start the testee as a separate process
> but loads it with dlopen(3) and calls the testee's main() function.

We specifically disallow this in current glibc because it does not
work in general=E2=80=94unless the application is really loadable as a shar=
ed
object (compiled as PIC and linked with -shared).