Hi, I noticed when building gzip with musl that gnulib is still replacing getopt and getopt_long. After some investigation, it looks to be because it expects getopt_long to accept ambiguous options with the same has_arg, flag, and val values[0]. The code responsible for this seems to only do this for getopt_long and not getopt_long_only[1]. I have no idea why, but since musl aims to conform to glibc's getopt_long behavior, we should probably do the same. [0] http://git.savannah.gnu.org/cgit/gnulib.git/tree/m4/getopt.m4#n313 [1] http://sourceware.org/git/?p=glibc.git;a=blob;f=posix/getopt.c;hb=HEAD#l562 -- Michael Forney