[gentoo-user] Profile 17.0, PIE, USE="pic", C(XX)FLAGS "-fpic", "-fPIC"?

[gentoo-user] Profile 17.0, PIE, USE="pic", C(XX)FLAGS "-fpic", "-fPIC"?

[Walter Dnes]

  If you execute...

grep ":pic " /usr/portage/profiles/use.local.desc

...you'll get multiple listings that mention...
- disable optimized assembly code that is not PIC friendly
- Force shared libraries to be built as PIC (this is slower)

  Question: does PIE imply pic/PIC?  I.e does a PIE build also require
USE="pic" and CFLAGS/CXXFLAGS="-fpic -fPIC"?  If so, is there a way to
disable PIE in profile 17.0?

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

[gentoo-user] Re: Profile 17.0, PIE, USE="pic", C(XX)FLAGS "-fpic", "-fPIC"?

[Martin Vaeth]

Walter Dnes <waltdnes@waltdnes.org> wrote:
>   Question: does PIE imply pic/PIC?

The code is somewhat different, but in principle yes.

> I.e does a PIE build also require USE="pic"

Assembler code which breaks pic will also break pie,
so better do not use that code.

> and CFLAGS/CXXFLAGS="-fpic -fPIC"?

These are usually added for libraries anyway.
They do not belong into your "manual" configuration file.

> If so, is there a way to disable PIE in profile 17.0?

If you want to switch it off for a particular binary,
there are -fno-PIE -no-pie.
Ebuilds should add it automatically if needed.
So far, I only needed it for clisp:
https://bugs.gentoo.org/show_bug.cgi?id=618170