This package is FTBFS on several architectures.
[ 3%] Building CXX object src/madness/world/CMakeFiles/MADworld-obj.dir/madness_exception.cc.o
cd /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/external/tinyxml && /usr/bin/c++ -DMAD_ROOT_DIR=\"/<<PKGBUILDDIR>>\" -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/external/tinyxml -I/<<PKGBUILDDIR>>/src/madness/external/tinyxml -I/<<PKGBUILDDIR>>/src -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src -g -O2 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -ffile-prefix-map=/<<PKGBUILDDIR>>=. -flto=auto -ffat-lto-objects -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -fdebug-prefix-map=/<<PKGBUILDDIR>>=/usr/src/madness-0.10.1+git20200818.eee5fd9f-4 -Wdate-time -D_FORTIFY_SOURCE=3 -std=c++17 -std=c++17 -fPIC -MD -MT src/madness/external/tinyxml/CMakeFiles/MADtinyxml-obj.dir/tinystr.cc.o -MF CMakeFiles/MADtinyxml-obj.dir/tinystr.cc.o.d -o CMakeFiles/MADtinyxml-obj.dir/tinystr.cc.o -c /<<PKGBUILDDIR>>/src/madness/external/tinyxml/tinystr.cc
cd /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/mra && /usr/bin/c++ -DMADNESS_MPI_HEADER=\"/usr/lib/x86_64-linux-gnu/mpich/include/mpi.h\" -DMAD_ROOT_DIR=\"/<<PKGBUILDDIR>>\" -DMPICH_SKIP_MPICXX=1 -DMRA_DATA_DIR=\"/<<PKGBUILDDIR>>/src/madness/mra\" -DOMPI_SKIP_MPICXX=1 -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/mra -I/<<PKGBUILDDIR>>/src/madness/mra -I/<<PKGBUILDDIR>>/src -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src -I/usr/lib/x86_64-linux-gnu/mpich/include -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/world -I/<<PKGBUILDDIR>>/src/madness/world -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/misc -I/<<PKGBUILDDIR>>/src/madness/misc -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/tensor -I/<<PKGBUILDDIR>>/src/madness/tensor -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/external/tinyxml -I/<<PKGBUILDDIR>>/src/madness/external/tinyxml -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/external/muParser -I/<<PKGBUILDDIR>>/src/madness/external/muParser -g -O2 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -ffile-prefix-map=/<<PKGBUILDDIR>>=. -flto=auto -ffat-lto-objects -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -fdebug-prefix-map=/<<PKGBUILDDIR>>=/usr/src/madness-0.10.1+git20200818.eee5fd9f-4 -Wdate-time -D_FORTIFY_SOURCE=3 -std=c++17 -std=c++17 -fPIC "-flto=auto -ffat-lto-objects" -MD -MT src/madness/mra/CMakeFiles/MADmra-obj.dir/mra1.cc.o -MF CMakeFiles/MADmra-obj.dir/mra1.cc.o.d -o CMakeFiles/MADmra-obj.dir/mra1.cc.o -c /<<PKGBUILDDIR>>/src/madness/mra/mra1.cc
cd /<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/world && /usr/bin/c++ -DMADNESS_MPI_HEADER=\"/usr/lib/x86_64-linux-gnu/mpich/include/mpi.h\" -DMAD_ROOT_DIR=\"/<<PKGBUILDDIR>>\" -DMPICH_SKIP_MPICXX=1 -DOMPI_SKIP_MPICXX=1 -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src/madness/world -I/<<PKGBUILDDIR>>/src/madness/world -I/<<PKGBUILDDIR>>/src -I/<<PKGBUILDDIR>>/obj-x86_64-linux-gnu/src -I/usr/lib/x86_64-linux-gnu/mpich/include -g -O2 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -ffile-prefix-map=/<<PKGBUILDDIR>>=. -flto=auto -ffat-lto-objects -fstack-protector-strong -fstack-clash-protection -Wformat -Werror=format-security -fcf-protection -fdebug-prefix-map=/<<PKGBUILDDIR>>=/usr/src/madness-0.10.1+git20200818.eee5fd9f-4 -Wdate-time -D_FORTIFY_SOURCE=3 -std=c++17 -std=c++17 -fPIC "-flto=auto -ffat-lto-objects" -MD -MT src/madness/world/CMakeFiles/MADworld-obj.dir/madness_exception.cc.o -MF CMakeFiles/MADworld-obj.dir/madness_exception.cc.o.d -o CMakeFiles/MADworld-obj.dir/madness_exception.cc.o -c /<<PKGBUILDDIR>>/src/madness/world/madness_exception.cc
[ 3%] Building CXX object src/madness/external/muParser/CMakeFiles/MADmuparser-obj.dir/muParserBase.cpp.o
cc1plus: error: unrecognized argument to ‘-flto=’ option: ‘auto -ffat-lto-objects’
cc1plus: error: unrecognized argument to ‘-flto=’ option: ‘auto -ffat-lto-objects’
Apparently, there is a rogue quoted "-flto=auto -ffat-lto-objects" flag in the build flags, which gcc is choking on. I couldn't pinpoint where that was getting injected.
Disabling LTO does not get rid of the quoted flag, nor does forcing the removal of this flag using DEB_CXX_MAINT_STRIP.
