Bug#1123920: carl9170fw: FTBFS with branch hardening

[Bastian Germann]

Source: carl9170fw
Version: 1.9.9-686-ge7ba7bf+dfsg-0.1
Severity: serious
Tags: ftbfs

The pkg fails to build because of flag -fcf-protection=full.
export DEB_BUILD_MAINT_OPTIONS=hardening=-branch solves the issue.