argp-standalone: option ARGP_NO_ERRS is not honoured
Username: Othmar Truniger
Origin: https://bugs.openwrt.org/index.php?do=details&task_id=1454
Symptom: error message is written for invalid option even with ARGP_NO_ERRS set in function argp_parse
Verified on ar71xx / mips_24kc / wndr3700 and mpc85xx / powerpc_8540 / tl-wdr4900
OpenWrt / LEDE trunk OpenWrt SNAPSHOT, r6548-8e1065d6
Found a problem when working with a software project where the LEDE / OpenWrt binary issues an error message for an invalid option when starting the binary while the debian / ubuntu linux version does not. I tracked it down to the fact that it must be a bug in the argp-standalone library of OpenWrt / LEDE where the option ARGP_NO_ERRS in function argp_parse is not honoured.
To reproduce I wrote a little demo program which works fine on debian and ubuntu but shows the invalid behaviour on OpenWrt / LEDE.
The demo program is hosted on
https://github.com/tru7/argp-demo
where I have also provided a feed named Makefile.lede to build the package on OpenWrt / LEDE.
I have no skills in coding and absolutely no skills in debugging, so this is about all I can do about this.