gettext

3cf8c327 - Fix undefined behaviour according to ISO C 23 § 6.5.6.(9).

Fix undefined behaviour according to ISO C 23 § 6.5.6.(9). Found by clang's undefined-behaviour sanitizer. * gettext-tools/src/msgl-fsearch.c (mult_index_list_accumulate): If len1 == 0, skip two loops.