"Unknown argument in the command line" build failure(s) — clang 6.0

gcc has plenty of options. Some of them should be implemented by clang, some other, no.
A first discussion occurred on this subject on the clang mailing list.
PackageVersionSupposed error messageFull log Bug report
adacontrol 1.19r10-2clang: error: unknown argument: '-gnatct' Log
adasockets 1.10.1-1clang: error: unknown argument: '-gnatea' Log
ahven 2.6-1.2error: unknown argument: '-gnatez'clang Log
alljoyn-gateway-1504 15.04~git20160606-4clang: error: unknown argument: '-print-multiarch' Log
anet 0.3.4-1clang: error: unknown argument: '-gnatea' Log
efitools 1.4.2-2clang: error: unknown argument: '-fno-toplevel-reorder' Log
fwupdate 10-3clang: error: unknown argument: '-maccumulate-outgoing-args' Log
gprbuild 2017-5clang: error: unknown argument: '-gnatea' Log
gprolog 1.4.5-4.1clang: error: unknown argument: '-ffixed-r12' Log
lastpass-cli 1.0.0-1.2clang: error: unknown argument: '-fno-aggressive-loop-optimizations' Log
libaws 17.2.2017-2clang: error: unknown argument: '-gnatea' Log
libgmpada 1.1-2clang: error: unknown argument: '-gnatea' Log
libi8x 0.0.5-1clang: error: unknown argument: '-fpreprocessed' Log
libxmlada 17.1.2017-5clang: error: unknown argument: '-gnatea' Log
music123 16.4-3clang: error: unknown argument: '-gnatea' Log
opencryptoki 3.8.1+dfsg-3clang: error: unknown argument: '-fgnu-tm' Log
pcscada 0.7.3-1.1clang: error: unknown argument: '-gnatea' Log
polyorb 2.11~20140418-5clang: error: unknown argument: '-gnats' Log
shim 0.9+1474479173.6c180c6-1clang: error: unknown argument: '-maccumulate-outgoing-args' Log
spark 2012.0.deb-11clang: error: unknown argument: '-gnatea' Log
thc-ipv6 3.4-1clang: error: unknown argument: '-freorder-blocks-and-partition' Log
topal 77-1clang: error: unknown argument: '-gnatea' Log

22 errors