Unsupported argument with another option - Rebuild of the Debian archive with clang

"Unsupported argument with another option" build failure(s)
clang 3.4.2

Versions: 2.9 - 3.0 - 3.1 - 3.2 - 3.3 - 3.4 - 3.4.2 - 3.5.0 - 3.6.0 - 3.8.1 - 3.9.1 - 4.0.1 - 5.0 - 6.0 - 8.0.1 - 9.0.1 - 10.0.0 - 11.0.0 - 12.0.1 - 13.0.0

Package	Version	Supposed error message	Full log
3dchess	0.8.1-18	clang: error: unsupported option '-fpcc-struct-return' for target 'x86_64-pc-linux-gnu'	Log
autodock-vina	1.1.2-3	clang: error: unsupported option '--lto'	Log
freecontact	1.0.21-3	clang: error: unsupported option '--help=optimizers'	Log
klibc	2.0.3-1	clang: error: unsupported option '--print-libgcc'	Log
libffi	3.1-2	clang: error: unsupported argument '--gdwarf2' to option 'Wa,'	Log
mlton	20100608-5.1	clang: error: unsupported option '-gstabs+'	Log
syslinux	3:6.03~pre14+dfsg-2	clang: error: unsupported option '--print-libgcc'	Log
validns	0.7-1	clang: error: unsupported option '--no-strict-aliasing'	Log

8 errors

Debian Package rebuild