Prevent loop exits from unwinding the context/scope stacks beyond a call_sv for smartmatch subs and class constructors #23204
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Leont
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Leont
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| "MULTICALL", | ||
| "REGCOMP", | ||
| "SMARTMATCH", | ||
| "CONSTRUCTOR" |
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does dump.c need an update?
dopoptoloop() or dopoptolabel() would find a loop outside the sub called from call_sv() and rewind the context and save stack to outside the context set up by call_sv(), crashes and panics ensure. Switching stacks here also starts a new context stack, so the outer loop isn't found and we don't crash. Most other callers to call_sv() (or call_method() etc) do the same. I'm not entirely sure about passing flags = 1 to push_stackinfo(), this matches pp_sort, but not other callers. Fixes Perl#16608
Using last, next etc would pop the context stack to above the call_sv(), generally resulting in a crash or assertion failure. The search the context to pop to stops at the top of the current context stack, and PUSHSTACKi() switches to a new stack, preventing the search from finding any loop outside the call_sv() Similar to Perl#16608
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smartmatch: fail to find the loop instead of crashing
dopoptoloop() or dopoptolabel() would find a loop outside the sub called from call_sv() and rewind the context and save stack to outside the context set up by call_sv(), crashes and panics ensure.
Switching stacks here also starts a new context stack, so the outer loop isn't found and we don't crash.
Most other callers to call_sv() (or call_method() etc) do the same.
I'm not entirely sure about passing flags = 1 to push_stackinfo(), this matches pp_sort, but not other callers.
Fixes #16608
class.c, injected_constructor: prevent loop exits exiting
Using last, next etc would pop the context stack to above the call_sv(), generally resulting in a crash or assertion failure.
The search the context to pop to stops at the top of the current context stack, and PUSHSTACKi() switches to a new stack, preventing the search from finding any loop outside the call_sv()
Similar to #16608
Also fixes a missing -DDEBUGGING string for PERLSI_REGCOMP