Incorrect handling of left shift overflow on non-x86_64 (returns value instead of runtime error)

[jcpunk]

Summary

On non-x86_64 architectures, Jsonnet does not raise a runtime error for integer left shift overflow. Instead, it returns a wrapped negative value and exits successfully (code 0). This contradicts expected behavior and causes regression test failure.

Affected Version:

• Jsonnet 0.22.0
• Observed on: non-x86_64 architectures (e.g., aarch64, ppc64le) in Fedora rawhide
• Not reproducible on: x86_64 (https://koji.fedoraproject.org/koji/taskinfo?taskID=143856012)

Reproduction:

jsonnet --ext-str var1=test --ext-code var2='{x:1,y:2}' error.integer_left_shift_runtime.jsonnet

Test case (error.integer_left_shift_runtime.jsonnet):

(1 << 63)

Built at:
https://koji.fedoraproject.org/koji/taskinfo?taskID=143856013
https://koji.fedoraproject.org/koji/taskinfo?taskID=143856014
https://koji.fedoraproject.org/koji/taskinfo?taskID=143856015

Which contains both a root.log showing installed packages and a build.log showing the output from the compile/test