RFR: JDK-8205055: Fix compilation optimization errors with new Solaris toolchain

[Magnus Ihse Bursie]

On 2018-06-15 01:26, gary.adams at oracle.com wrote:
> Locally tested the fix below and via mach5 jobs.
> The ~50 failed tests all completed successfully.
> It'd be good for Erik to repeat his full testing with
> this patch included in case it blocked other issues
> from being observed.
>
> This fix can be integrated after the sync from jdk/client.
>
>  Issue: https://bugs.openjdk.java.net/browse/JDK-8205055
>
> Proposed fix:
>
> diff --git a/make/hotspot/lib/JvmOverrideFiles.gmk 
> b/make/hotspot/lib/JvmOverrideFiles.gmk
> --- a/make/hotspot/lib/JvmOverrideFiles.gmk
> +++ b/make/hotspot/lib/JvmOverrideFiles.gmk
> @@ -74,6 +74,8 @@
>
>  else ifeq ($(OPENJDK_TARGET_OS), solaris)
>    ifneq ($(DEBUG_LEVEL), slowdebug)
> + # dev studio 12.6 workaround
> + BUILD_LIBJVM_arguments.cpp_OPTIMIZATION := LOW

The if should test
ifeq ($(TOOLCHAIN_TYPE), solstudio)
since this is a compiler issue, not an OS issue.

Ideally, it should also test if using version 12.6, but unfortunately 
there's currently no elegant way of expressing that in the makefiles, so 
I'm OK with the workaround of just having a comment. I assume, from the 
name and a quick glance at the file, that the contents makes it unlikely 
that a lowevered optimization level wouldprovoke a performance 
regression in pre-12.6 solstudio compilations.

Still, it would be nice if you are able to drill down the issue to 
figure out exactly why a higher optimization level causes this file to 
be incorrectly compiled. It might be code in hotspot with undefined 
behavior, or it might be bugs in solstudio. In any case, it should be 
addressed. As an initial fix to allow compilation to proceed, this is 
fine, though.

/Magnus