diff -Naur ansifilter-2.13.orig/src/makefile ansifilter-2.13/src/makefile
--- ansifilter-2.13.orig/src/makefile	2019-01-06 19:54:57.946093219 -0500
+++ ansifilter-2.13/src/makefile	2019-01-06 19:57:48.501622737 -0500
@@ -8,12 +8,12 @@
 #CC=clang++
 
 # Added -std=c++11 because of auto_ptr to unique_ptr transition
-CXXFLAGS= -Wall -O2 -DNDEBUG -std=c++11 -fPIC
+CXXFLAGS+= -Wall -O2 -DNDEBUG -std=c++11 -fPIC
 #CXXFLAGS= -O0 -ggdb -std=c++11 -fPIC
 #CXXFLAGS="-DNDEBUG -g2 -O3 -march=i686" 
 #cov-build --dir cov-int make -j 2
 
-LDFLAGS=
+LDFLAGS+=
 
 SOURCES=arg_parser.o stringtools.o cmdlineoptions.o main.o platform_fs.o\
 codegenerator.o htmlgenerator.o pangogenerator.o texgenerator.o latexgenerator.o rtfgenerator.o\