Q: What does "no method return value" mean in Eclipse Debug perspective? Placing a breakpoint in a method which is run by multiple threads, I encountered for the first time a "no method return value" Name in the Variables tab:

What does it mean?
Acting, breakpoints in other places behave normally and do not produce this message.
Why am I seeing this?

UPDATE:
I found the answer for "Why I am seeing this?":
As I clarified in the comment below, the aforementioned method does return a value. However, it is static and despite clean build of the entire project building it, I could not get rid of that weird "no method return value" thing.
Only after I did clean build of all projects in my workspace, did this message disappear and was replaced by the normal variables names and values display.
Any answer that could explain why an entire workspace clean build is mandated and why "no method return value" instead of some other (more descriptive) message, will be accepted.

A: The return value is displayed when you step over the end of a non-void method.
For example, when the debugger stops at a breakpoint there is no method return value:

but when you step over the end of the method via Step Return (F7) or at the end of a method via Step Over (F6), the method return value is shown:

