Bug#884795: patman: FTBFS on x32: final link failed: Nonrepresentable section

Source: patman
Version: 1.2.2+dfsg-2
Severity: important
Justification: fails to build from source
User: [email protected]
Usertags: x32

The build of patman for x32 (admittedly not a release architecture)
failed:

  g++ -DVERSION="\"1.2\"" -Wdate-time -D_FORTIFY_SOURCE=2 -Wall  -O3 -funroll-loops -DNDEBUG -c -o prefix_tree.o prefix_tree.cpp
  g++ -DVERSION="\"1.2\"" -Wdate-time -D_FORTIFY_SOURCE=2 -Wall  -O3 -funroll-loops -DNDEBUG -c -o fasta.o fasta.cpp
  g++ -DVERSION="\"1.2\"" -Wdate-time -D_FORTIFY_SOURCE=2 -Wall  -O3 -funroll-loops -DNDEBUG -c -o main.o main.cpp
  g++ -Wdate-time -D_FORTIFY_SOURCE=2 -Wall  -O3 -funroll-loops -DNDEBUG -o patman prefix_tree.o fasta.o main.o -specs=/usr/share/dpkg/pie-link.specs -Wl,-z,relro -Wl,-z,now -lpopt
  /usr/bin/ld: prefix_tree.o: relocation R_X86_64_32S against `.rodata' can not be used when making a shared object; recompile with -fPIC
  /usr/bin/ld: final link failed: Nonrepresentable section on output
  collect2: error: ld returned 1 exit status
  Makefile:22: recipe for target 'patman' failed

The problem appears to be that patman links with -fPIE (via
pie-link.specs) but does not compile with any such option.  (GCC, at
least in Debian, now defaults to -fPIE on most architectures, but not
yet on x32.)

Could you please take a look?

Thanks!