[erlang-questions] Feedback wanted: Remove compilation times from BEAM files in OTP 19?

[Björn Gustavsson]

On Fri, Apr 8, 2016 at 1:16 PM, Loïc Hoguin <essen@REDACTED> wrote:
> The build time is occasionally useful but the same can be achieved by
> looking at the beam file creation or modification time.
>
> Is it just the build time though?
>
> Wouldn't these infos also be a problem?

Yes, some of them are potential problems.

> * Auto generated vsn (it looks like repeated builds keep the same version
> number if the source doesn't change, but is that guaranteed?)
>

Yes, it is guaranteed as long as the compiler
generates the code in the same way. That is,
new optimizations could change it (but in that
case, there would be other changes in the BEAM
file as well).

>      [{vsn,[192941001008994618371492498907572068968]},
>
> * Compiler version (if two different compiler versions produce the same
> result except for the compiler version, this is a waste; if compiler version
> of a build is desirable it should probably be kept separate)
>
>      {version,"6.0.1"},
>
> * Compile options with paths
>
>      {outdir,"/build/erlang/src/otp/lib/ssl/src/../ebin"},
>      {i,"/build/erlang/src/otp/lib/kernel/src"},
>
> * Source file name
>
>      {source,"/build/erlang/src/otp/lib/ssl/src/ssl.erl"}]},
>

/Bjorn