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2.5 * "ab" hangs forever

print(2.5 * "ab")     # CPython: TypeError    pxx: no output, never terminates

Killed at a 10s timeout with no output. 3 * "ab" (int repeat) is fine; it is the FLOAT count that hangs — presumably the repeat loop counts down a value converted from a double and never reaches its bound.

A hang is worse than a wrong answer in one respect: an ordinary test run just stops, with nothing to diff. This one was found only because the operator sweep ran each program under timeout.

Whatever the eventual policy on mismatched operand types (see [[bug-nilpy-mixed-type-arithmetic-silently-does-pointer-math]]), the repeat count must be bounded before the loop, not trusted.

Gate

make test-nilpy + self-host byte-identical, plus a regression test that runs under a timeout.

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