New hotspot build only builds "PRODUCT"

[Erik Joelsson]

On 2015-05-05 18:12, Volker Simonis wrote:
> On Tue, May 5, 2015 at 3:31 PM, Magnus Ihse Bursie
> <magnus.ihse.bursie at oracle.com> wrote:
> OK, I see so I won't mess with debug builds then:)
I think leaving debug builds until we are at the stage of organizing 
flags better is OK. Some flags will come from configure, some are based 
on debug level etc.
> But another question: I just compared the dependencies compiler flags
> of the old and the new build and realized that for the old build we
> use '-MMD -MP -MF -fpch-deps' but in the new build we only use '-MMD
> -MF' (except for x86 which is the only platform in the new build where
> we still use -fpch-deps). Is this intentional as well?
>
> I think the omission of -MP may be related to "8072106: Properly
> handle dependencies for deleted header files" which created the
> corresponding targets manually. But what about '-fpch-deps', shouldn't
> we always use it?
As Magnus said, -MP is more efficient, but we have a general solution 
that achieves the same thing for all platforms already.

Regarding -fpch-deps, I think we should not use it if we declare proper 
dependencies from header files to precompiled header and from 
precompiled header to object files using it. It would just be redundant 
and with the amount of header files being included everywhere in 
hotspot, redundancy in dependency file generation is not something we 
need. I think the current dependency makefiles are already around 50MB!

/Erik