Verbose Build Logs
Initially proposed and based on the feedback accepted for jessie in https://lists.debian.org/debian-devel/2013/06/msg00539.html
Looking at the build log, you often just see
CC ... CCLD ... (sometimes even colorized)
This doesn't really help when trying to diagnose things, and even for successful builds it's valuable to have the complete build log, including the parts how the upstream build system is called from the Debian packaging.
Verbose build logs allow to analyse package builds and give hints to more issues regarding the build, especially for the hardening flags. The lintian hardening checks are incomplete, because they rely on the inspection of the generated binaries, which may be incomplete especially for many plugins or dynamically loadable extensions.
For jessie we will:
File and track issues for packages not enabling verbose builds. https://qa.debian.org/bls/bytag/W-compiler-flags-hidden.html
Fix debhelper not passing --disable-silent-rules by default (#680686). cdbs already does this.
Fix debhelper to show how the upstream build system is called (#680687). As an alternative buildds could run with DEB_BUILD_OPTIONS=verbose.
Change Debian policy to recommend or require verbose build logs. Preferring to make this a requirement. See #628515.
This is not rocket science, but allows for almost free additional QA. Size of the build logs is not an issue.