ONIGENC_SUPPORT_AMBIG_FLAG  291 mbstring/oniguruma/oniguruma.h #define ONIGENC_SUPPORT_AMBIG_FLAG(enc)     ONIGENC_AMBIGUOUS_MATCH_ASCII_CASE
ONIGENC_SUPPORT_AMBIG_FLAG  361 mbstring/oniguruma/oniguruma.h #define ONIGENC_SUPPORT_AMBIG_FLAG(enc)        ((enc)->support_ambig_flag)