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In commit 9479b6d5e08eacce06c6ab60abc9b2f4eb8b71e4 we updated all of the collation data to harmonize with the new version of ISO 14651 which is derived from Unicode 9.0.0. This collation update brought with it some changes to locales which were not desirable by some users, in particular it altered the meaning of the locale-dependent-range regular expression, namely [a-z] and [A-Z], and for en_US it caused uppercase letters to be matched by [a-z] for the first time. The matching of uppercase letters by [a-z] is something which is already known to users of other locales which have this property, but this change could cause significant problems to en_US and other similar locales that had never had this change before. Whether this behaviour is desirable or not is contentious and GNU Awk has this to say on the topic: https://www.gnu.org/software/gawk/manual/html_node/Ranges-and-Locales.html While the POSIX standard also has this further to say: "RE Bracket Expression": http://pubs.opengroup.org/onlinepubs/9699919799/xrat/V4_xbd_chap09.html "The current standard leaves unspecified the behavior of a range expression outside the POSIX locale. ... As noted above, efforts were made to resolve the differences, but no solution has been found that would be specific enough to allow for portable software while not invalidating existing implementations." In glibc we implement the requirement of ISO POSIX-2:1993 and use collation element order (CEO) to construct the range expression, the API internally is __collseq_table_lookup(). The fact that we use CEO and also have 4-level weights on each collation rule means that we can in practice reorder the collation rules in iso14651_t1_common (the new data) to provide consistent range expression resolution *and* the weights should maintain the expected total order. Therefore this patch does three things: * Reorder the collation rules for the LATIN script in iso14651_t1_common to deinterlace uppercase and lowercase letters in the collation element orders. * Adds new test data en_US.UTF-8.in for sort-test.sh which exercises strcoll* and strxfrm* and ensures the ISO 14651 collation remains. * Add back tests to tst-fnmatch.input and tst-regexloc.c which exercise that [a-z] does not match A or Z. The reordering of the ISO 14651 data is done in an entirely mechanical fashion using the following program attached to the bug: https://sourceware.org/bugzilla/show_bug.cgi?id=23393#c28 It is up for discussion if the iso14651_t1_common data should be refined further to have 3 very tight collation element ranges that include only a-z, A-Z, and 0-9, which would implement the solution sought after in: https://sourceware.org/bugzilla/show_bug.cgi?id=23393#c12 No regressions on x86_64. Verified that removal of the iso14651_t1_common change causes tst-fnmatch to regress with: 422: fnmatch ("[a-z]", "A", 0) = 0 (FAIL, expected FNM_NOMATCH) *** ... 425: fnmatch ("[A-Z]", "z", 0) = 0 (FAIL, expected FNM_NOMATCH) *** --- ChangeLog | 11 + localedata/Makefile | 1 + localedata/en_US.UTF-8.in | 2159 +++++++++++++++++++++++++++++++++ localedata/locales/iso14651_t1_common | 1928 ++++++++++++++--------------- posix/tst-fnmatch.input | 125 +- posix/tst-regexloc.c | 8 +- 6 files changed, 3224 insertions(+), 1008 deletions(-) create mode 100644 localedata/en_US.UTF-8.in I'm suggesting this change immediately for 2.28 to avoid further problems with users expectations and sorting with [a-z] and [A-Z] until a clearer consensus can be reached for a final solution. File attached as .tar.gz to get past spam detectors. There is a lot of UTF-8 data in en_US.UTF-8 (every possible character in the LATIN set that can be sorted with the existing test case infrastructure). -- Cheers, Carlos.
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