From Jason Yong <Jason_Yong@uk.ibm.com> on build-dev:

Hello,
 
I've had an issue where I've had a custom extension to CompileJavaModules.gmk with the variable java.base_COPY set to files that I wanted to be copied across but its value was overwritten by CompileJavaModules.gmk.
 
I would like to propose changes that would allow a custom extensions to update variables listed in CompileJavaModules.gmk. This issue is similar to bug JDK-8064372 (https://bugs.openjdk.java.net/browse/JDK-8064372) but affects all the other variables such as:
 
java.activation_SETUP
java.base_ADD_JAVAC_FLAGS
java.base_COPY
java.base_CLEAN
etc
 
The fix is also similar, changing := to += allowing the custom extension to append to the variable if already set and create it if its not.
I would appreciate any feedback and help on what the next steps would be.

Thanks

Jason