Friday, September 28, 2012

Scary: GWT Team does not fix serious GWT Compiler Bugs


After finishing development on my GWT (2.4) project, I found out, that the compiled version does not work exactly as in the development mode.

Some method ( isValid() ) seems not to be called.

Calling code (simplified):

boolean valid=true;
if(! mypanel.isValid())


public boolean isValid()
    return true;

This works well in development mode, but in compiled code, isValid() was never called. From this point things got strange. I've added a log-command to the method:

public boolean isValid()
    updateSomeData();"method called");
    return true;

The method was called and the log entry written.

I removed the log entry and changed the calling part to:

boolean valid=true;
boolean x=mypanel.isValid();

Now again the method was called. This seems to be some problem in the compiler optimizer. After switching off the optimizer, the compiled code did work as expected.

After searching the web, I found an issue report, DESCRIBING THE EXACT SAME PROBLEM !


So this is a know issue since over a year and present since GWT 2.3 !!!

I have not problem with bugs, but I can't understand, why no one seems to care. Can there be something more serious, than a compiler-bug ?

If you search the database, there are some compiler / optimizer issues, that seem not to have been fixed.


This is scary ! If you can't trust the compiler, you'll never know, if your code works in production as I did under development. Adding / removing a single line may change the whole behavior. Testing will become a nightmare !

Some one should care.



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