When trying to compile ruby from a fresh checkout, with the Unicode version changed to 9.0.0, I get the following error:
./miniruby.exe -I./lib -I. -I.ext/common ./tool/enc-unicode.rb --header ./enc/unicode/data/9.0.0 > enc/unicode/9.0.0/name2ctype.h
/bin/sh: ./miniruby.exe: No such file or directory
make[1]: *** [uncommon.mk:1110: enc/unicode/9.0.0/name2ctype.h] Error 127
make[1]: Leaving directory '/cygdrive/c/Data/ruby_test9'
make: *** [uncommon.mk:1104: enc/unicode/9.0.0/name2ctype.h] Error 2
./miniruby.exe is not yet available, but there is an attempt to use it. I think the solution is to either use base ruby here, or to delay the production of the files derived from Unicode data files to a later stage.
I do not get this error from a preexisting checkout, obviously because ./miniruby already exists. But this problem should also affect continuous integration, unless it is for some reason cygwin-specific.
I'm attaching a configuration summary and the full make output.
I apologize for having pressed the submit button erroneously when I barely started writing this bug report.
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