Warning in `Python/executor_cases.c.h`

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'initializing': conversion from 'uint64_t' to 'uint32_t', possible loss of data (compiling source file ..\Python\ceval.c)

[D:\a\cpython\cpython\PCbuild\_freeze_module.vcxproj]

Appears in #106262.

Linked PRs

• gh-106267: Add explicit type cast #106289

[Eclips4]

cc @brandtbucher @gvanrossum

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Code which generate this:

cpython/Tools/cases_generator/generate_cases.py

Lines 522 to 523 in a8ae739

	else:
	out.emit(f"{typ}{ceffect.name} = operand;")

Probably, we need explicit type cast here. For example, something like that:

out.emit(f"{typ}{ceffect.name} = ({typ.strip()}) operand;")

But it seems useless when typ coincide with operand type.

[gvanrossum]

Thanks! Maybe Formatter.cast() can be used? If you can figure out how, feel free to submit a PR.

[Eclips4]

Thanks! Maybe Formatter.cast() can be used? If you can figure out how, feel free to submit a PR.

Unfortunately Formatter.cast() cannot be used here. Formatter.cast() is destined for StackEffect, which have type field. In our case, we have an list of ActiveCacheEffect instances, which doesn't have an type field.

There's type is based on how much bits we have. If we have < 64 bits, the type is f"uint{bits}_t". In this case we have an 32 bits, so computed type is uint32_t. Is this works as intended?

[gvanrossum]

Okay, can you submit a PR? Your initial solution is fine -- there is actually no chance that typ is uint64_t, so there's no need to make the cast conditional. Thanks for finding this!

[gvanrossum]

(Oh, we normally don't write a space between the cast and the variable.)

[Eclips4]

Okay, can you submit a PR?

Done!