Stackoverflow in RascalMPL while running the test framework

[BlackHart98]

I encountered this exception while testing my pretty printer module in rascal:

java.lang.StackOverflowErrorjava.lang.StackOverflowError                                  
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowErrorjava.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModules
(internal error)
        at $shell$(|main://$shell$|)

java.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModules
/ testing 1/3 error: testAlterV @ |file:///Users/pius/Desktop/Dev/ptlbase/ptlbase/src/lang/spark/prettyprint/Tests.rsc|(444,123,<17,0>,<20,1>)
        Could not initialize class java.lang.StackTraceElement$HashedModules
java.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModules
Unexpected (uncaught) exception, closing the REPL: 
java.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModulesjava.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModules
java.io.IOException: Stream closed
Exception in thread "main" java.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModules

Exception: java.lang.NoClassDefFoundError thrown from the UncaughtExceptionHandler in thread "main"

I only get this issue when increased the number of test. If you need a link to the project I am willing to provide that.

• Context: VSCode plugin, Command-line REPL
• Rascal Version 0.33.7, stable

[DavyLandman]

I think it would be nice to share your project, as quite some stuff is going wrong here.

[BlackHart98]

I will do that soon, thanks

On Wed, 28 Feb 2024 at 15:40, Davy Landman @.***> wrote:

I think it would be nice to share your project, as quite some stuff is going wrong here.

— Reply to this email directly, view it on GitHub https://github.com/usethesource/rascal/issues/1920#issuecomment-1969129858, or unsubscribe https://github.com/notifications/unsubscribe-auth/ADVANN5TVJB3ZEW4EC54GCDYV46VHAVCNFSM6AAAAABD6BZ4ZWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTSNRZGEZDSOBVHA . You are receiving this because you authored the thread.Message ID: @.***>

[BlackHart98]

Here is the like to the project

https://github.com/BlackHart98/sqlpolyglot/blob/main/src/main/rascal/spark/prettyprint/Tests.rsc#L8

[DavyLandman]

Does it also happen if you call testCreateDB() directly?

[jurgenvinju]

I reproduced the behavior. The stackoverflows happen when this test is called:

test bool testAlterV() {
  loc file = |project://sqlpolyglot/src/main/rascal/spark/examples/alterv.ssql|;
  return prettyCond(file);
}

if I remove this test, everything runs smoothly.

[jurgenvinju]

The trigger is this definition which results in an infinite recursion:

public str toString(ViewId viewId)="<toString(viewId)>";

I found this by setting :set debugging true in VScode and stepping through the code (with "step into"), until I got stuck myself in this place :-)

The stackoverflow error thus genuine, so that's not the bug, but the report of this stackoverflow is bad. It should have given a stack trace like so:

...  toString(ViewId viewId)
...  toString(ViewId viewId)
...  toString(ViewId viewId)
...  toString(ViewId viewId)
...  toString(ViewId viewId)
...

Such than easy diagnosis can be made. I'll look into fixing that in the Rascal interpreter. In the mean time this definition would be a good workaround:

public str toString(propRef(list[Identifier] ids))="<for (id <- ids) {><id> <}>"[..-1];

[jurgenvinju]

Looks like an interesting project @BlackHart98 !

[jurgenvinju]

Simple reproduction:

rascal>int f(int i) = f(i);
int (int): function(|prompt:///|(0,20,<1,0>,<1,20>))
rascal>f(2)
java.lang.StackOverflowErrorjava.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.StackOverflowError
java.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModules
(internal error)
        at $shell$(|main://$shell$|)

java.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModules
Unexpected (uncaught) exception, closing the REPL: 
java.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModulesjava.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModules
java.io.IOException: Stream closed
Exception in thread "main" java.lang.NoClassDefFoundError: Could not initialize class java.lang.StackTraceElement$HashedModules

Exception: java.lang.NoClassDefFoundError thrown from the UncaughtExceptionHandler in thread "main"

[jurgenvinju]

The problem seems to be this code which catches the StackOverflowError just below the deepest stack frame, and then calls more code which needs stack space to print the error:

In Expression.CallOrTree.interpret():

catch (StackOverflowError e) {
                e.printStackTrace();
                throw RuntimeExceptionFactory.stackOverflow(this, eval.getStackTrace());
            }

[BlackHart98]

The trigger is this definition which results in an infinite recursion:

public str toString(ViewId viewId)="<toString(viewId)>";

I found this by setting :set debugging true in VScode and stepping through the code (with "step into"), until I got stuck myself in this place :-)

The stackoverflow error thus genuine, so that's not the bug, but the report of this stackoverflow is bad. It should have given a stack trace like so:

...  toString(ViewId viewId)
...  toString(ViewId viewId)
...  toString(ViewId viewId)
...  toString(ViewId viewId)
...  toString(ViewId viewId)
...

Such than easy diagnosis can be made. I'll look into fixing that in the Rascal interpreter. In the mean time this definition would be a good workaround:

public str toString(propRef(list[Identifier] ids))="<for (id <- ids) {><id> <}>"[..-1];

Yeah figured that out belatedly, but like you said the report is bad but is genuine

[jurgenvinju]

Thinking about the fix now. not so easy :-) I need to get some stack space to create the error, but I also need the information on the stack to create the error message.

[BlackHart98]

Looks like an interesting project @BlackHart98 !

I also noticed that Rascal resolves the project a lot slower, hat could be the issue?

[jurgenvinju]

@blackhart98 I don't know. What do you mean by "resolves the project". Is that the code for starting a terminal or when you read a file with the project:/// scheme? or something else? It's unrelated to this I think, but could also be interesting to look at in a different issue :-)

Thanks for reporting this one anyway. The solution is underway but I need some advice from @DavyLandman to finalize it.

[BlackHart98]

@BlackHart98 I don't know. What do you mean by "resolves the project". Is that the code for starting a terminal or when you read a file with the project:/// scheme? or something else? It's unrelated to this I think, but could also be interesting to look at in a different issue :-)

Thanks for reporting this one anyway. The solution is underway but I need some advice from @DavyLandman to finalize it.

Maybe my choice of word was wrong, what I meant is the it takes time to load the rascal project after I save changes(on VSCode)

[jurgenvinju]

Ah yes. No that's a "feature" of the slow type-checker. The more modules you edit, the more it needs to type-check and the slower it becomes. We are working on a compiled version of that as we speak to make that faster.

[jurgenvinju]

If you keep the .tpl files in your target folder, the type-checker will reuse as much as possible. So that helps. I'd put the target folder in your .gitignore and remove it from git with git rm -r target. That way the time stamps of the .tpl files stay in order when you git pull or git push and you have less work for the typechecker usually.

[BlackHart98]

Thanks, :-)