gh-140868: Don't rely on undefined left shift behavior in assert#140869
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| PyStackRef_TagInt(intptr_t i) | ||
| { | ||
| assert(Py_ARITHMETIC_RIGHT_SHIFT(intptr_t, (i << Py_TAGGED_SHIFT), Py_TAGGED_SHIFT) == i); | ||
| assert(Py_ARITHMETIC_RIGHT_SHIFT(intptr_t, (intptr_t)(((uintptr_t)i) << Py_TAGGED_SHIFT), |
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All I did was run the build in our default settings at work! 😀
Fidget-Spinner
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StanFromIreland
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python#140869) Don't rely on undefined left shift behavior in assert
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This assert https://github.com/python/cpython/blob/main/Include/internal/pycore_stackref.h#L406 contains a left shift of a potentially negative value which is undefined behavior. The non-assert line does a uintptr_t cast to avoid the undefined behavior. Replicate that in the assert and then cast the final value back to intptr_t.