Preventing the build from adding options like '-pipe' et al

[Ralph Seichter]

Hello,

I maintain the Unit ebuild for Gentoo Linux, and I am currently trying
to figure out how to prevent the configure/build process from extending
compiler or linker flags. I use

  ./configure --cc-opt="${CFLAGS}" --ld-opt="${LDFLAGS}" [...]

to pass Gentoo's user-defined options along, but find that flags like
'-pipe' or '-g' are being added without my say-so.

Gentoo QA is quite rigorous about not allowing builds to use options not
provided by the user, so I am looking for the best way to enforce this
restriction. Can any of you provide me with pointers? Thanks.

-Ralph