RFR : 8218136: minor hotspot adjustments for xlclang++ from xlc16 on AIX

Thu Jan 31 20:18:48 UTC 2019

Ah, IBM is starting to use clang? That's nice! From what I understand after a quick search, this also means that gcc/clang options are available, and recommended [1] to use. It would be really nice if we could align the xlc options more closely to gcc/clang. 

/Magnus

[1] https://www.ibm.com/support/knowledgecenter/SSGH3R_16.1.0/com.ibm.xlcpp161.aix.doc/migrate/xlC_vs_xlclangpp.html

> 31 jan. 2019 kl. 15:50 skrev Baesken, Matthias <matthias.baesken at sap.com>:
> 
> Please review  this small webrev  . It contains a few changes  for  building hotspot   on AIX with  xlclang++  / xlc16  .
> ( most likely switching to   xlclang++  / xlc16    will be a must once  we introduce C++11/14 features )
> 
> Some comments on the changes :
> 
> 
> - porting_aix.cpp  :  workaround for demangle.h (does not work with xlclang++)
> 
> - arguments.cpp/hpp  :  the UNSUPPORTED_OPTON macro lead  to assigning false to  AllocateHeapAt which is a bad idea (and does not work with xlclang++)
> 
> -   globalDefinitions_xlc.hpp   : xlclang++ sets   __GNUC__ so we must not  have #error ... in this case
> 
> 
> 
> 
> Bug/webrev :
> 
> https://bugs.openjdk.java.net/browse/JDK-8218136
> 
> http://cr.openjdk.java.net/~mbaesken/webrevs/8218136.0/
> 
> 
> Thanks, Matthias
> 