Perl_scalarvoid: turn OP_STUB into OP_NULL #23759
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An OP_STUB in void context is functionally identical to an OP_NULL. It's straightforward and safe to transform an OP_STUB into an OP_NULL by adding an extra `case` within `Perl_scalarvoid`. In doing so: * The redundant OPs are more likely to be omitted from the op_next chain. * The OP tree is more consistent with `assert` expectations in `Perl_rpeep`. (The programs in GH Perl#17228 no longer trigger assertions.)
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tonycoz
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This looks reasonable.
I thought some CPAN modules might have troubles, but the only ones I could see that weren't obsolete and check for OP_STUB (lots create OP_STUB) were Want, autovivification and Scope::Upper and they all built/tested fine with this change.
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An OP_STUB in void context is functionally identical to an OP_NULL.
It's straightforward and safe to transform an OP_STUB into an OP_NULL by adding an extra
casewithinPerl_scalarvoid. In doing so:assertexpectations inPerl_rpeep. ( Closes op.c:16388: Perl_rpeep: Assertion `oldop->op_type == OP_NEXTSTATE || oldop->op_type == OP_DBSTATE' failed. #17228 )