Stop using precompiled headers for Linux?
erik.joelsson at oracle.com
Mon Nov 5 16:46:24 UTC 2018
On 2018-11-03 01:51, Magnus Ihse Bursie wrote:
> On 2018-10-30 20:21, Erik Joelsson wrote:
>> Last I checked, it did provide significant build speed improvements
>> when building just hotspot, but that could need revisiting.
>> We do have verification of --disable-precompiled-headers (in
>> slowdebug) in builds-tier2 so we normally get notified if this fails.
>> However, Mach5 has not been running since Friday so this particular
>> bug wasn't detected automatically. Looking at the bug, it also failed
>> on Solaris, which would have been caught by tier1 builds.
> If we decide to keep precompiled headers on by default, maybe we
> should add a simple no-PCH verification task in tier1? It only needs
> to build hotspot, so it should be quick.
That is a good point, so sure we can do that. Which debug level would be
most appropriate for this test, debug or slowdebug? I very much doubt
it's relevant to run release builds without PCH.
>> On 2018-10-30 10:26, Ioi Lam wrote:
>>> Is there any advantage of using precompiled headers on Linux? It's
>>> on by default and we keep having breakage where someone would forget
>>> to add #include. The latest instance is JDK-8213148.
>>> I just turn on precompiled headers explicitly in all my builds. I
>>> don't see any difference in build time (at least not significant
>>> enough for me to bother).
>>> Should we disable it by default on Linux?
>>> - Ioi
More information about the build-dev