RFR: 8247910: Improve alignment and power-of-2 utilities using C++14

[Thomas Stüfe]

On Wed, Sep 23, 2020, 16:43 Kim Barrett <kim.barrett at oracle.com> wrote:

> > On Sep 23, 2020, at 2:14 AM, Thomas Stüfe <thomas.stuefe at gmail.com>
> wrote:
> >
> > Hi,
> >
> > unfortunately this breaks my builds on Ubuntu 16.4. I am using gcc 5.4.0
> which according to https://openjdk.java.net/groups/build/doc/building.html
> should still be an accepted compiler?
> >
> > Creating hotspot/variant-server/libjvm/gtest/gtestLauncher from 1 file(s)
> > In file included from
> /shared/projects/openjdk/jdk-jep387/source/src/hotspot/share/services/memTracker.hpp:85:0,
> >                  from
> /shared/projects/openjdk/jdk-jep387/source/src/hotspot/share/precompiled/precompiled.hpp:60:
> >
> /shared/projects/openjdk/jdk-jep387/source/src/hotspot/share/services/mallocTracker.hpp:190:78:
> error: size of array '_snapshot' is not an integral constant-expression
> >    static size_t _snapshot[CALC_OBJ_SIZE_IN_TYPE(MallocMemorySnapshot,
> size_t)];
>
> I don’t see anything here to indicate what platform this is for.  It’s
> not, by any chance, arm32?
>

Sorry. No, plain old x64.

Upgrading to gcc 7 also fixed another problem I had where the gtests would
not be buildable for non-pch builds. So I guess gcc 5 support slowly
bitrots.

Unfortunately I do not have time to follow up on this. Maybe later.

That is, Thomas