compiler info in kernel identification string

Erik Cederstrand erik at
Fri Nov 16 10:43:28 UTC 2012

Den 16/11/2012 kl. 11.18 skrev Andriy Gapon <avg at>:

> This is starting to turn into a bikeshed, but anyway...
> on 16/11/2012 12:00 Daniel Braniss said the following:
>> the question as to what compiler was used to compile the kernel is a bit of an
>> oxymoron, since the kernel is made up of many different modules, which get 
>> compiled
>> either by different compilers, or different compiler flags.
> The canonical way to compile a kernel is to use buildkernel and compile modules
> along with the kernel.  Other configurations are supported too, of course.
>> since the compiler does 'sign' the modules it compiles (and clang will/should
>> do it soon: some tool like
>> file(1) could be modified to provide it, or config -x (8) ...
> The key word in your note about clang is 'soon' as in 'not yet'.
> Besides, when I see a bug report with a dmesg *I* want to immediately know what
> compiler was used there.

But wouldn't you want to know the compiler flags, too? And the kernel config file?  src.conf? Local patches? To solve a bug, in general you would want sufficient information to recreate the environment locally. Compiler version is not enough.

So either you have all information in every binary, because they might have been built outside a buildworld, or you have the general buildworld / buildkernel configuration in a central place and expect users to supply information about whatever non-standard setup they did.


More information about the freebsd-current mailing list