LD: Cannot add content to ctors section

[Ben Hirschberg]

It is not working, because Alpine container images are using musl-libc. The dynamic loader in musl doesn't call the functions in ".init_array", it delegates this requirement to C runtime (crt0.o). It works in case of Alpine executable which was linked against musl's crt0, because musl's crt0 calls ".init_array" functions.

In my project I have a shared object which is loaded into a Go application. Go application does not use crt0.o and does not call ".init_array" functions. They say that it is ok, because this is the responsibility of the dynamic loader. (see this discussion if you're interested https://github.com/golang/go/issues/28909)

I want to do a workaround this issue and put my static constructors into ".ctros" section because it is supported across the board.



-----Original Message-----
From: H.J. Lu <hjl.tools@gmail.com>
Sent: Wednesday, May 20, 2020 3:12 PM
To: Ben Hirschberg <bhirschb@cyberarmor.io>
Cc: binutils@sourceware.org
Subject: Re: LD: Cannot add content to ctors section

On Wed, May 20, 2020 at 4:52 AM Ben Hirschberg <bhirschb@cyberarmor.io> wrote:
>
> Yeah, well, if life was so easy...
>
> The original solution was using C with attribute constructor. It it is not working in this scenario because it adds the function to the ".init_array" section and not the ".ctors".
>

Why didn't .init_array work?

--
H.J.
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