Bug#897706: arachne-pnr: ftbfs with GCC-8

[Matthias Klose]

Package: src:arachne-pnr
Version: 0.1+20160813git52e69ed-1
Severity: normal
Tags: sid buster
User: debian-gcc at lists.debian.org
Usertags: ftbfs-gcc-8

Please keep this issue open in the bug tracker for the package it
was filed for.  If a fix in another package is required, please
file a bug for the other package (or clone), and add a block in this
package. Please keep the issue open until the package can be built in
a follow-up test rebuild.

The package fails to build in a test rebuild on at least amd64 with
gcc-8/g++-8, but succeeds to build with gcc-7/g++-7. The
severity of this report will be raised before the buster release.

The full build log can be found at:
http://aws-logs.debian.net/2018/05/01/gcc8/arachne-pnr_0.1+20160813git52e69ed-1_unstable_gcc8.log.gz
The last lines of the build log are at the end of this report.

To build with GCC 8, either set CC=gcc-8 CXX=g++-8 explicitly,
or install the gcc, g++, gfortran, ... packages from experimental.

  apt-get -t=experimental install g++ 

Common build failures are new warnings resulting in build failures with
-Werror turned on, or new/dropped symbols in Debian symbols files.
For other C/C++ related build failures see the porting guide at
http://gcc.gnu.org/gcc-8/porting_to.html

[...]
dpkg-buildpackage
-----------------

dpkg-buildpackage: info: source package arachne-pnr
dpkg-buildpackage: info: source version 0.1+20160813git52e69ed-1
dpkg-buildpackage: info: source distribution unstable
dpkg-buildpackage: info: source changed by Ruben Undheim <ruben.undheim at gmail.com>
 dpkg-source --before-build arachne-pnr-0.1+20160813git52e69ed
dpkg-buildpackage: info: host architecture amd64
 fakeroot debian/rules clean
dh clean 
   debian/rules override_dh_auto_clean
make[1]: Entering directory '/<<BUILDDIR>>/arachne-pnr-0.1+20160813git52e69ed'
dh_auto_clean
	make -j1 clean
make[2]: Entering directory '/<<BUILDDIR>>/arachne-pnr-0.1+20160813git52e69ed'
rm -f src/*.o tests/*.o src/*.d tests/*.d bin/arachne-pnr
rm -f tests/test_bv tests/test_us
rm -f share/arachne-pnr/*.bin
rm -f src/version_*
make[2]: Leaving directory '/<<BUILDDIR>>/arachne-pnr-0.1+20160813git52e69ed'
rm -f debian/man/*.1
rm -f -r share/
make[1]: Leaving directory '/<<BUILDDIR>>/arachne-pnr-0.1+20160813git52e69ed'
   dh_clean
 debian/rules build-arch
dh build-arch 
   dh_update_autotools_config -a
   dh_auto_configure -a
   dh_auto_build -a
	make -j1
make[1]: Entering directory '/<<BUILDDIR>>/arachne-pnr-0.1+20160813git52e69ed'
g++ -g -O2 -fdebug-prefix-map=/<<BUILDDIR>>/arachne-pnr-0.1+20160813git52e69ed=. -fstack-protector-strong -Wformat -Werror=format-security -Isrc -std=c++11 -Wall -Wshadow -Wsign-compare -Werror -Wdate-time -D_FORTIFY_SOURCE=2  -c -o src/arachne-pnr.o src/arachne-pnr.cc
In file included from /usr/include/c++/8/set:60,
                 from src/util.hh:25,
                 from src/bstream.hh:19,
                 from src/vector.hh:19,
                 from src/netlist.hh:21,
                 from src/arachne-pnr.cc:16:
/usr/include/c++/8/bits/stl_tree.h: In instantiation of 'class std::_Rb_tree<Port*, Port*, std::_Identity<Port*>, IdLess, std::allocator<Port*> >':
/usr/include/c++/8/bits/stl_set.h:133:17:   required from 'class std::set<Port*, IdLess>'
src/netlist.hh:158:28:   required from here
/usr/include/c++/8/bits/stl_tree.h:452:21: error: static assertion failed: comparison object must be invocable with two arguments of key type
       static_assert(__is_invocable<_Compare&, const _Key&, const _Key&>{},
                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
make[1]: *** [<builtin>: src/arachne-pnr.o] Error 1
make[1]: Leaving directory '/<<BUILDDIR>>/arachne-pnr-0.1+20160813git52e69ed'
dh_auto_build: make -j1 returned exit code 2
make: *** [debian/rules:11: build-arch] Error 2
dpkg-buildpackage: error: debian/rules build-arch subprocess returned exit status 2