* configure.ac: Don’t suppress -Wsystem-headers since Gnulib no
longer enables it.
nw="$nw -Wtraditional" # Warns on #elif which we use often
nw="$nw -Wcast-qual" # Too many warnings for now
nw="$nw -Wconversion" # Too many warnings for now
- nw="$nw -Wsystem-headers" # Don't let system headers trigger warnings
nw="$nw -Wsign-conversion" # Too many warnings for now
nw="$nw -Wtraditional-conversion" # Too many warnings for now
nw="$nw -Wunreachable-code" # Too many warnings for now