On Fri, Feb 28, 2020 at 4:40 PM Martin Buchholz <marti...@google.com> wrote: > > LGTM.
Thanks, for your review Martin. > We're all resisting the urge to modernize this test. I have some more zip-related fixes in the queue :) > > On Fri, Feb 28, 2020 at 5:17 AM Volker Simonis <volker.simo...@gmail.com> > wrote: >> >> Hi, >> >> can I please get a review for this trivial test fix: >> >> http://cr.openjdk.java.net/~simonis/webrevs/2020/8240226/ >> https://bugs.openjdk.java.net/browse/JDK-8240226 >> >> The SkipBytes() subtest in DeflateIn_InflateOut.java executes several >> steps and for each step it deflates an array of 1024*1024 bytes. In >> every step, before deflation is performed, the array is refilled with >> random bytes. However, only after the first step, the size of the >> generated, deflated stream is checked and recorded. The following >> subtests all assume that deflating the array filled with the same >> number of, but different, random bytes will produce a deflated stream >> of the same size. >> >> This assumption is wrong. Depending on the exact contents of the >> source array, the size of the generated, deflated result might >> slightly differ. For some reason, the deflated result produced by the >> default zlib implementation seems to always have the same size >> (although there's no guarantee for this), but other zlib >> implementations sometimes produce differently sized, deflated results. >> >> The problem can easily be reproduced by placing a version of >> Cloudflare's zlib clone (https://github.com/cloudflare/zlib) on the >> LD_LIBRARY_PATH (for jdk versions configured with >> "--with-zlib=system", which is the default since jdk11): >> >> $ LD_LIBRARY_PATH=/ziptests/build/zlib-cloudflare >> ./images/jdk/bin/java DeflateIn_InflateOut >> java.lang.Exception: Stack trace >> at java.base/java.lang.Thread.dumpStack(Thread.java:1379) >> at DeflateIn_InflateOut.fail(DeflateIn_InflateOut.java:235) >> at DeflateIn_InflateOut.check(DeflateIn_InflateOut.java:238) >> at DeflateIn_InflateOut.SkipBytes(DeflateIn_InflateOut.java:204) >> at DeflateIn_InflateOut.realMain(DeflateIn_InflateOut.java:229) >> at DeflateIn_InflateOut.main(DeflateIn_InflateOut.java:243) >> >> Passed = 16 failed = 1 >> Exception in thread "main" java.lang.AssertionError: Some tests failed >> at DeflateIn_InflateOut.main(DeflateIn_InflateOut.java:245) >> >> The test may (and actually does) randomly fail at any of the subtests >> executed in SkipBytes() which reuse "numReadable", the size of the >> first deflated stream generated in that method. >> >> The fix is trivial. It is unnecessary to refill the source array with >> random bytes before each subtest. Filling the array one time at test >> startup time should be sufficient. >> >> Thank you and best regards, >> Volker
