Re: [tycho-user] please test staged Tycho 2.0.0

[Pierre-Charles David <pierre-charles.david@xxxxxxx>]

Le 16/08/2020 à 22:57, Mickael Istria a écrit :
> Java 13 was never supported by Tycho, because it has never been 
> necessary so far.
> Tycho 1.7.0 was trying to be more tolerant and was resolving against a 
> different EE without warning much; while it worked, this was a 
> confusing state both for usage and maintenance of Tycho. But with 
> Tycho 2.0, EE management becomes more strict (and more clear/simple), 
> so it now uses JavaSE-13 to try to resolve dependencies if running 
> with Java 13, and since JavaSE-13 isn't supported by Tycho, it just 
> fails with an explicit message.


Thanks for the information.


I was under the impression that using toolchains would allow to 
workaround this, and in particular to decouple the JVM version *running* 
Tycho from the Java profile used to compile and resolve dependencies. 
I'm not familiar with Tycho internals, but I expected that pointing 
Tycho, through a toolchain, to a specific JVM installation would make it 
use that for the EE to use instead of either a hard-coded profile or 
"the currently running VM".

That's what I understood from 
https://wiki.eclipse.org/Tycho/Release_Notes/2.0#Resolve_system.packages_from_Execution_Envionment_against_toolchain_or_current_JRE.2C_from_Java_13, 
but I tried adding this to my parent POM:

  <plugin>
    <groupId>org.eclipse.tycho</groupId>
    <artifactId>tycho-compiler-plugin</artifactId>
    <version>${tycho-version}</version>
    <configuration>
<requireJREPackageImports>true</requireJREPackageImports>
    </configuration>
  </plugin>

and the build still fails with: Java 13.0.2 executing Tycho 2.0 to build 
Java 8 sources, with *I think* a correctly configured toolchain for 
JavaSE-1.8.

Is this not how it's configured, or am I misunderstanding something?