[Nix-dev] Patching uname in stdenv?

[Michael Raskin]

>> What would people think of a patch that made stdenv's uname return the
>> same value on every linux?
>
>I assume you're referring to the kernel version returned by ‘uname -r’.
>
>Since ‘uname’ is also used outside of builders, this is not a good idea — it 
>would change the behaviour that users expect from it.

We already have distinct bash in stdenv and user's environment. The 
same could be done for uname.

>BTW, the kernel version does matter sometimes, for instance, APR (IIRC) at 
>compile-time decides whether to use the accept4() system call based on the 
>kernel version of the build system.  So if you try to run the resulting library 
>on an older kernel, it doesn't work.  Arguably the kernel version should be part 
>of the "system" value, but that would be too painful.

In some sense, we have no idea whether our stdenv works on kernels 
older than our kernelHeaders. So the same version can be used as 
baseline for uname in stdenv.