Fedora 31 Self-Contained Change proposal: Add LLD As Update Alternatives Option For LD

[Ben Cotton]

https://fedoraproject.org/wiki/Changes/Add_LLD_As_Update_Alternatives_Opt...

== Summary ==
Allow users to optionally use update-alternatives to make /usr/bin/ld
point to /usr/bin/lld.

== Owner ==
* Name: [[User:tstellar| Tom Stellard]]
* Email: <tstellar(a)redhat.com&gt;

== Detailed Description ==
Update the lld package %post and %postun steps to configure the system
so that a user can use the update-alternatives tool to create a
symlink from /usr/bin/ld to /usr/bin/lld.  This will effectively allow
lld to act as the system linker and make it easier for users to
integrate lld into their projects.  This same functionality is
currently available with one other non-system linker: gold.

I want to be clear that this proposal is not about making lld the
system linker or using lld during brew builds.  This is simply about
making it easier for end-users to use lld with their own projects.

== Benefit to Fedora ==
This change will make it much easier for users to try out lld in their
projects.  Many build systems and compilers assume that the linker is
/usr/bin/ld, and it is very difficult to seamlessly integrate lld into
existing build systems.  With this proposal a user will be able to
easily switch between ld.bfd and lld without having to make any
modifications to their build systems.

== Scope ==
* Proposal owners: tstellar
* Other developers: N/A (not a System Wide Change)
* Release engineering:
* Policies and guidelines: N/A
* Trademark approval: N/A (not needed for this Change)

== Upgrade/compatibility impact ==
N/A (not a System Wide Change)

== How To Test ==
Tests for this change will be added to the lld package's CI tests.
One test will install lld and verify that /usr/bin/ld.bfd is still the
system linker.  Another test will use update-alternatives to update
/usr/bin/ld to point to /usr/bin/lld and then it will run /usr/bin/ld
--version to verify that this correctly points to lld and then link a
simple program with it.

== User Experience ==
This will greatly enhance the experience for users who want to use
lld.  They will be able to try lld with their projects by simply
running `update-alternatives --set ld /usr/bin/lld` instead of having
to make modifications to existing build systems.

== Dependencies ==
N/A (not a System Wide Change)

== Contingency Plan ==
* Contingency mechanism: (What to do?  Who will do it?) N/A (not a
System Wide Change)
* Contingency deadline: N/A (not a System Wide Change)
* Blocks release? N/A (not a System Wide Change)
* Blocks product? N/A

-- 
Ben Cotton
He / Him / His
Fedora Program Manager
Red Hat
TZ=America/Indiana/Indianapolis

[Stephen John Smoogen]

On Tue, 23 Jul 2019 at 09:33, Ben Cotton <bcotton(a)redhat.com&gt; wrote:

>  https://fedoraproject.org/wiki/Changes/Add_LLD_As_Update_Alternatives_Opt...
>
>
>  == Dependencies ==
>  N/A (not a System Wide Change)
>
>  
I am not sure about this. We are looking at making a system-wide change of
having /usr/bin/ld be a symlink to /etc/alternatives/ld with all the
headaches of where it should work but doesn't for a multitude of little
reasons.


-- 
Stephen J Smoogen.

[Neal Gompa]

On Tue, Jul 23, 2019 at 10:28 AM Stephen John Smoogen <smooge(a)gmail.com&gt; wrote:
>  On Tue, 23 Jul 2019 at 09:33, Ben Cotton <bcotton(a)redhat.com&gt; wrote:
> >
> > https://fedoraproject.org/wiki/Changes/Add_LLD_As_Update_Alternatives_Opt...
> >
> >
> > == Dependencies ==
> > N/A (not a System Wide Change)
> >
>
>  I am not sure about this. We are looking at making a system-wide change of having
> /usr/bin/ld be a symlink to /etc/alternatives/ld with all the headaches of where it should
> work but doesn't for a multitude of little reasons.
>  
Isn't it already this way?



-- 
真実はいつも一つ！/ Always, there's only one truth!

[Stephen John Smoogen]

On Tue, 23 Jul 2019 at 11:10, Neal Gompa <ngompa13(a)gmail.com&gt; wrote:

>  On Tue, Jul 23, 2019 at 10:28 AM Stephen John Smoogen
> <smooge(a)gmail.com&gt;
>  wrote:
>  >
>  >
>  >
>  > On Tue, 23 Jul 2019 at 09:33, Ben Cotton <bcotton(a)redhat.com&gt; wrote:
>  >>
>  >>
>  https://fedoraproject.org/wiki/Changes/Add_LLD_As_Update_Alternatives_Opt...
>  >>
>  >>
>  >> == Dependencies ==
>  >> N/A (not a System Wide Change)
>  >>
>  >
>  > I am not sure about this. We are looking at making a system-wide change
>  of having /usr/bin/ld be a symlink to /etc/alternatives/ld with all the
>  headaches of where it should work but doesn't for a multitude of little
>  reasons.
>  >
>
>  Isn't it already this way?
>  

You know what helps.. looking at the right system before making an email
about this being a system wide change. You are correct Neal:

[smooge@fedora00 ~]$ ls -l /usr/bin/ld
lrwxrwxrwx. 1 root root 20 Jul 19 18:51 /usr/bin/ld -> /etc/alternatives/ld

{ I was on a CentOS-6 box when I checked and thought I was on my F30 box }

-- 
Stephen J Smoogen.