calling an undeclared routine in the REPL undeclares all variables

[stuart-little]

The Problem

As the title says: after calling foo(<argument>) for an undefined subroutine foo results in previously-defined variables (unrelated to &f) henceforth registering as undefined.

Expected Behavior

Defined variables unaffected.

Actual Behavior

Defined variables rendered undefined.

Steps to Reproduce

Full REPL session:

> my ($x,$y,$z) = 42, 'string', (1,2,3)              
(42 string (1 2 3))
> 'boo'.&foo
===SORRY!=== Error while compiling:
Undeclared routine:                                      
          foo used at line 2                               
> $x
===SORRY!=== Error while compiling:
Variable '$x' is not declared
------> <BOL>⏏$x
> $y                                                 
===SORRY!=== Error while compiling:
Variable '$y' is not declared                       
 ------> <BOL>⏏$y
> $z                                                 
===SORRY!=== Error while compiling:
Variable '$z' is not declared
------> <BOL>⏏$z

Environment

• Operating system: x86_64 GNU/Linux
• Compiler version (perl6 -v or raku -v):

Welcome to Rakudo(tm) v2020.11-95-g6c7044ec3.
Implementing the Raku(tm) programming language v6.d. 
Built on MoarVM version 2020.11-47-g1c7358004.

(compiled from this repo minutes ago, as I type this)

[lizmat]

Is this a recent change in behaviour?

[stuart-little]

I certainly don't recall seeing it before, but I compile often; it's hard to keep track of when things change..

[Altai-man]

It is a regression, 2020.10 is clear.

[stuart-little]

And actually, it doesn't seem to have much to do specifically with subroutines:

> my $x=12
12
> $y
===SORRY!=== Error while compiling:
Variable '$y' is not declared
at line 2
------> <BOL>⏏$y
> $x
===SORRY!=== Error while compiling:
Variable '$x' is not declared
------> <BOL>⏏$x

Calling an undeclared variable in general seems to undeclare other variables..