[perl #79908] Stop sub inlining from breaking closures

When a closure closes over a variable, it references the variable
itself, as opposed to taking a snapshot of its value.

This was broken by the constant optimisation added for
constant.pm’s sake:

{
    my $x;
    sub () { $x };  # takes a snapshot of the current value of $x
}

constant.pm no longer uses that mechanism, except on older perls, so
we can remove this hack, causing code like this this to start work-
ing again:

BEGIN{
    my $x = 5;
    *foo = sub(){$x};
    $x = 6
}
print foo; # now prints 6, not 5

1 files changed, 1 insertions, 1 deletions

diff --git a/proto.h b/proto.h
index aca70305a4..15ec0735d9 100644
--- a/proto.h
+++ b/proto.h
@@ -3003,7 +3003,7 @@ PERL_CALLCONV void	Perl_op_clear(pTHX_ OP* o)
 #define PERL_ARGS_ASSERT_OP_CLEAR	\
 	assert(o)
 
-PERL_CALLCONV SV*	Perl_op_const_sv(pTHX_ const OP* o, CV* cv)
+PERL_CALLCONV SV*	Perl_op_const_sv(pTHX_ const OP* o)
 			__attribute__warn_unused_result__;
 
 PERL_CALLCONV OP*	Perl_op_contextualize(pTHX_ OP* o, I32 context)