A DESCRIPTION OF THE PROBLEM :
When trying to run javac with multiple annotation processors, only some of which have been modularized, it's impossible to run the modularized ones off of --processor-module-path: using "--processor-path" for the unmodularized ones gives "error: illegal combination of -processorpath and --processor-module-path", and using "--class-path" gives "error: plug-in not found: ErrorProne".

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. download the JARs for Lombok and Error Prone:
    https://projectlombok.org/downloads/lombok.jar
    https://repo1.maven.org/maven2/com/google/errorprone/error_prone_core/2.5.1/error_prone_core-2.5.1-with-dependencies.jar
    https://repo1.maven.org/maven2/org/checkerframework/dataflow-shaded/3.7.1/dataflow-shaded-3.7.1.jar
    https://repo1.maven.org/maven2/com/google/code/findbugs/jFormatString/3.0.0/jFormatString-3.0.0.jar
2. create a file Foo.java in the same folder with the contents as given below
3. run Lombok only: javac --processor-module-path lombok.jar --class-path lombok.jar Foo.java
4. add Error Prone: javac -XDcompilePolicy=simple --processor-path error_prone_core-2.5.1-with-dependencies.jar;dataflow-shaded-3.7.1.jar;jFormatString-3.0.0.jar -Xplugin:ErrorProne --processor-module-path lombok.jar --class-path lombok.jar Foo.java
5. move Lombok from --processor-module-path to --processor-path: javac -XDcompilePolicy=simple --processor-path error_prone_core-2.5.1-with-dependencies.jar;dataflow-shaded-3.7.1.jar;jFormatString-3.0.0.jar;lombok.jar -Xplugin:ErrorProne --class-path lombok.jar Foo.java


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The javac invocation in step 4 works and the result is the same as the one of step 5.
ACTUAL -
The javac invocation in step 4 fails with:
error: illegal combination of -processorpath and --processor-module-path

---------- BEGIN SOURCE ----------
import lombok.Data;
import java.util.Set;

@Data
class Foo {
    public static void main(String... args) {
        Set<Long> values = Set.of();
        if (values.contains(42)) {
            System.out.println("Hello world!");
        }
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Run modular annotation processors off of --processor-path as well