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From: Florian Weimer <fweimer@redhat.com>
To: vincent Dupaquis <v.dupaquis@trusted-objects.com>
Cc: <gcc-help@gcc.gnu.org>
Subject: Re: Question related to -fPIC behaviour across architectures
References: <CAH9OHLJ_EnbTA6Ga8w77tGEijjHYadB8s_1dk4TLUH5oCGS5Ew@mail.gmail.com>
 <7038357f-02af-0bcd-f156-73851c3227b3@trusted-objects.com>
Date: Tue, 03 May 2022 16:29:58 +0200
In-Reply-To: <7038357f-02af-0bcd-f156-73851c3227b3@trusted-objects.com>
 (vincent Dupaquis's message of "Tue, 3 May 2022 10:26:25 +0200")
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* vincent Dupaquis:

> - Did I miss anything ?

The linker can perform relaxations (e.g., elimination of GOT
indirection) based on whole-program analysis, something the compiler
cannot do.  Such optimizations are very much target-dependent, and they
often need some previous ABI work to define new relaxable relocations
for relocatable object files.

> - Is there somewhere a common definition of what mean PIC for the
>   different architectures ?

Not really, not even for ELF.  There are some common assumptions in the
background for ELF implementations (e.g., one canonical function
address), but how you get there varies somewhat.

Thanks,
Florian