gh-104619: never leak comprehension locals to outer locals() #104637
Merged
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The initial implementation of PEP 709 didn't bother to clear comprehension locals after an inlined comprehension, if the name was a global outside the comprehension. This was purely an optimization to save a couple extra instructions in this case; it didn't seem necessary to clear the comprehension value, since outer references to the name would use
LOAD_GLOBAL
anyway and not see the value in fastlocals.But it is necessary to clear the comprehension local even in this case, because otherwise it will still show up in
locals()
, or in debugger usage, outside of the comprehension.