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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug pch/108732] Pre-compiled headers cannot be output to /dev/null
Date: Wed, 08 Feb 2023 23:01:19 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108732

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Matt Hellige from comment #5)
> That makes sense, but it's just a strange inconsistency from a usability
> point of view.
>=20
> .so files are generally mmapped as well, I believe, aren't they? But I can
> still generate one to /dev/null if I like:
>=20
>    $ gcc12.2.0 -o /dev/null -rdynamic -shared foo.o bar.o -lrt ...
>=20
> Works fine.

Well so works differently because the linker produces runtime relocations f=
or
some segments of the shared objects which get applied at runtime. This is
unlike pch which does have a relocation method but that method is slow. Also
the linker is basically doing copies from other files into the final file w=
hile
gcc is outputting its internals out for pch.=