With fresh ports:

# cd /usr/ports/print/cups-filters 
# make


causes this error

file included from filter/pdftoopvp/pdftoopvp.cxx:24:
/usr/local/include/poppler/PDFDoc.h:306:3: warning: 'long long' is a C++11 extension [-Wc++11-long-long]
  long long strToLongLong(char *s);
  ^
In file included from filter/pdftoopvp/pdftoopvp.cxx:26:
In file included from ./filter/pdftoopvp/oprs/OPRS.h:19:
./filter/pdftoopvp/oprs/OPVPSplash.h:37:1: warning: class 'SplashGlyphBitmap' was previously declared as a struct [-Wmismatched-tags]
class SplashGlyphBitmap;
^
/usr/local/include/poppler/splash/Splash.h:38:8: note: previous use is here
struct SplashGlyphBitmap;
       ^
In file included from filter/pdftoopvp/pdftoopvp.cxx:27:
filter/pdftoopvp/OPVPOutputDev.h:81:16: warning: 'OPVPOutputDev::startPage' hides overloaded virtual function [-Woverloaded-virtual]
  virtual void startPage(int pageNum, GfxState *state);
               ^
/usr/local/include/poppler/OutputDev.h:147:16: note: hidden overloaded virtual function 'OutputDev::startPage' declared here: different number of parameters (3 vs 2)
  virtual void startPage(int pageNum, GfxState *state, XRef *xref) {}
               ^
In file included from filter/pdftoopvp/pdftoopvp.cxx:31:
filter/pdftoopvp/OPVPError.h:39:23: warning: variadic macros are a C99 feature [-Wvariadic-macros]
#define opvpError(pos,...) error(errInternal,pos,__VA_ARGS__)
                      ^
filter/pdftoopvp/pdftoopvp.cxx:617:30: warning: conversion from string literal to 'char *' is deprecated [-Wdeprecated-writable-strings]
  globalParams->setAntialias("no");
                             ^
11 warnings generated.
  CXXLD    pdftoopvp
  CXX      pdftopdf-pdftopdf.o
  CXX      pdftopdf-pdftopdf_jcl.o
  CXX      pdftopdf-pdftopdf_processor.o
In file included from filter/pdftopdf/pdftopdf_processor.cc:2:
filter/pdftopdf/qpdf_pdftopdf_processor.h:5:10: fatal error: 'qpdf/QPDF.hh' file not found
#include <qpdf/QPDF.hh>
         ^
1 error generated.
*** Error code 1

Stop.
make[3]: stopped in /usr/ports/print/cups-filters/work/cups-filters-1.0.58
*** Error code 1

Stop.
make[2]: stopped in /usr/ports/print/cups-filters/work/cups-filters-1.0.58
*** Error code 1

Stop.
make[1]: stopped in /usr/ports/print/cups-filters
*** Error code 1

Stop.
make: stopped in /usr/ports/print/cups-filters
[root@moby /usr/ports/print/cups-filters]#