[pypy-issue] Issue #1919: Problematic strings returned from os.read (pypy/pypy)
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Sat Nov 1 20:13:21 CET 2014
New issue 1919: Problematic strings returned from os.read
Here's a nasty one. The attached script fails on recent pypys (result in d should be True).
tannit can reproduce it w/ a recent pypy2 no-jit build:
(it may take no more than a few tries before it prints a bogus result of "False\nTrue")
AFAICT the rpython level string's hash code seems bogus. The bad string's from an os.read w/ count 1 specified resulting in a string of length 1.
I haven't tracked down to when this began happening but I recall it beginning to exhibit itself on PyPy3 at least a couple weeks ago in the most unrelated way (backspace in pyrepl began raising an exception). Doesn't happen in 2.4.0 release (pypy2 & pypy3)
I suspect the pinning/zeroing changes aren't clearing out the initial hash code but that's just a guess, so far I can't see how that would even happen
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