[MCOMPILER-336] Dependency that should be on modulepath sometime put on classpath

• Type: Task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.7.0
• Fix Version/s: 3.8.0
• Assignee: Robert Scholte
• Reporter: Martin Desruisseaux
• Created: 12/Apr/18 10:44
• Updated: 06/Jun/18 19:42
• Resolved: 18/May/18 08:35

Description

maven-compiler-plugin sometime puts modularized dependencies on the javac -classpath option instead than -modulepath, which cause compilation failure. A test case is attached. Step to reproduce:

cd module-vs-classpath
cd a
mvn install
cd ../b
mvn clean install
mvn install

The last command fail with the following error message:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.7.0:compile (default-compile) on project b: Compilation failure
[ERROR] module not found: test.a

Execution with the -X option shows that the test.a dependency is correctly declared in -modulepath when executing mvn clean install, but is wrongly declared in -classpath when executing mvn install.

A workaround is to remove the <useIncrementalCompilation>false</useIncrementalCompilation> option in the pom.xml files, or to execute touch src/main/java/module-info.java before mvn install. However the same error message occurs when attempting to execute mvn site, for which case I have found no workaround yet (note: the mvn site problem is not reproduced by the attached module-vs-classpath.zip file).