Notes for g2 - reproducible builds result

Version annotated: 0.72-5
Identified issues:
Identifier: records_build_flags
Description Records $CFLAGS, which vary intentionally due to the «-fdebug-prefix-map=${BUILDPATH}=.»,
«-ffile-prefix-map=${BUILDPATH}=.» or «-fmacro-prefix-map=${BUILDPATH}=.» flags.
.
We have a patch pending to GCC to fix this issue centrally:
.
https://gcc.gnu.org/ml/gcc-patches/2016-11/msg00182.html
.
Though the patch is currently unlikely to be merged. If/when this
is accepted, this issue should be fixed for all packages and you
should not need to fix it specifically in your package.
.
There is also a work-in-progress patch to dpkg that could address this issue:
.
https://bugs.debian.org/985553
.
For more background information see:
.
• https://alioth-lists.debian.net/pipermail/reproducible-builds/Week-of-Mon-20160822/006788.html
• https://alioth-lists.debian.net/pipermail/reproducible-builds/Week-of-Mon-20160905/006984.html
• https://alioth-lists.debian.net/pipermail/reproducible-builds/Week-of-Mon-20160912/007076.html
Identifier: gcc_captures_build_path
Description Captures build path, e.g., /build/1st/foo-42.0 v. /build/foo-42.0/2nd
.
Until early 2024 we varied the build path when testing packages from unstable
and experimental, which we have stopped doing now as the build path is recorded
as part of the environment and thus can be used when rebuilding.
.
This issue is kept here for the time being.
.
dpkg-buildflags version 1.20.6+ sets -ffile-prefix-map by default
(and -fdebug-prefix-map in older versions) which fixes this issue
in many cases, but not all (see: records_build_flags).
.
There are patches submitted upstream to address this specific issue, but they
are unlikely to be merged at this point:
.
https://gcc.gnu.org/ml/gcc-patches/2017-04/msg00513.html
.
When this is accepted into GCC upstream, we could remove this note.
In the meantime, please do not remove this issue, nor mark it as deterministic,
nor untag these packages.
 

Our notes about issues affecting packages are stored in notes.git and are targeted at packages in Debian in 'unstable/amd64' (unless they say otherwise).