I suspect this is a compiler bug in compact string intrinsics, because it reproduces only with C1. Starts to pass with `-XX:-CompactStrings` (which disables compact strings). Starts to pass `-XX:-Inline` (which disables intrinsics). Starts to pass with `-XX:DisableIntrinsic=_getCharStringU`.

Reproduces reliably after JDK-8268698, but the issue could manifest after JDK-8141132 in any unlucky code.

% CONF=linux-x86_64-server-fastdebug make images test TEST="java/time/test/java/time/format/TestUnicodeExtension.java" TEST_VM_OPTS="-XX:TieredStopAtLevel=1"

...

est test.java.time.format.TestUnicodeExtension.test_withLocale(dz, null, null, null, null, "??????????, ????????2017 ??????????? ????10 ??????? 3 ?????? 15:00 ?????? ???????????????????????????????????????"): failure
java.time.format.DateTimeParseException: Text '??????????, ????????2017 ??????????? ????10 ??????? 3 ?????? 15:...' could not be parsed at index 74

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java/time/test/java/time/format/TestUnicodeExtension.java
Total tests run: 531, Passes: 519, Failures: 12, Skips: 0
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