[ipxe-devel] BUILD_ID_CMD := perl -e 'printf "0x%08x", int ( rand ( 0xffffffff ) ); '

[Christian Nilsson]

On Sat, 19 Jan 2019 at 13:03, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
> Hello Michael,
>
> Linux distributions are struggling hard to create reproducible builds.
> This means if you run the make script twice you should get exactly the
> same binary. Cf. https://wiki.debian.org/ReproducibleBuilds
>
> Currently iPXE is introducing a random number as build id:
>
> # Command to generate build ID.  Must be unique for each $(BIN)/%.tmp,
> # even within the same build run.
> #
> BUILD_ID_CMD    := perl -e 'printf "0x%08x", int ( rand ( 0xffffffff ) );'
>
> Random number do not give any guarantee that they are unique. So this is
> not only disadvantageous for creating reproducible builds but simply buggy.
>
> A better solution would be to simply delete temporary files.
>
> Best regards
>
> Heinrich

This has already been discussed several times, and no-one has so far
provided an alternate fix for the need of this.
How would deleting temporary files fix the need for ROMs to see if
they are initializing the same or different instances of the ROM?
http://lists.ipxe.org/pipermail/ipxe-devel/2015-February/003978.html

Another recent PR which eliminates the randomness but then creates the
issues that the randomness is needed for:
http://lists.ipxe.org/pipermail/ipxe-devel/2018-October/006323.html

Commit that introduced this is
https://git.ipxe.org/ipxe.git/commitdiff/58f6e553625c90d928ddd54b8f31634a5b26f05e