Re: Order changes in PG16 since ICU introduction

Jeff Davis <pgsql@j-davis.com> writes:
> === 0001: do not convert C to en-US-u-va-posix

> I plan to commit this soon.

Several buildfarm animals have failed since this went in.  The
only one showing enough info to diagnose is siskin [1]:

@@ -1043,16 +1043,15 @@
 ERROR:  ICU locale "nonsense-nowhere" has unknown language "nonsense"
 HINT:  To disable ICU locale validation, set parameter icu_validation_level to DISABLED.
 CREATE COLLATION testx (provider = icu, locale = 'C'); -- fails
-ERROR:  could not convert locale name "C" to language tag: U_ILLEGAL_ARGUMENT_ERROR
+NOTICE:  using standard form "en-US-u-va-posix" for locale "C"
 CREATE COLLATION testx (provider = icu, locale = '@colStrength=primary;nonsense=yes'); -- fails
 ERROR:  could not convert locale name "@colStrength=primary;nonsense=yes" to language tag: U_ILLEGAL_ARGUMENT_ERROR
 SET icu_validation_level = WARNING;
 CREATE COLLATION testx (provider = icu, locale = '@colStrength=primary;nonsense=yes'); DROP COLLATION testx;
 WARNING:  could not convert locale name "@colStrength=primary;nonsense=yes" to language tag: U_ILLEGAL_ARGUMENT_ERROR
+ERROR:  collation "testx" already exists
 CREATE COLLATION testx (provider = icu, locale = 'C'); DROP COLLATION testx;
-WARNING:  could not convert locale name "C" to language tag: U_ILLEGAL_ARGUMENT_ERROR
-WARNING:  ICU locale "C" has unknown language "c"
-HINT:  To disable ICU locale validation, set parameter icu_validation_level to DISABLED.
+NOTICE:  using standard form "en-US-u-va-posix" for locale "C"
 CREATE COLLATION testx (provider = icu, locale = 'nonsense-nowhere'); DROP COLLATION testx;
 WARNING:  ICU locale "nonsense-nowhere" has unknown language "nonsense"
 HINT:  To disable ICU locale validation, set parameter icu_validation_level to DISABLED.

I suppose this is environment-dependent.  Sadly, the buildfarm
client does not show the prevailing LANG or LC_XXX settings.

            regards, tom lane

[1] https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=siskin&dt=2023-05-08%2020%3A09%3A26