--- a/src/Makefile
+++ b/src/Makefile
@@ -46,12 +46,12 @@ flif: $(FILES_O) flif.o
 
 # Command-line FLIF decoding tool - Apache2 (not built by default)
 dflif: $(FILES_H) libflif_dec$(LIBEXT) flif.cpp
-	$(CXX) -std=gnu++11 $(CXXFLAGS) $(OPTIMIZATIONS) -DDECODER_ONLY -g0 -Wall flif.cpp $(LDFLAGS) -L. -lflif_dec -o dflif
+	$(CXX) -std=gnu++11 $(CXXFLAGS) $(CPPFLAGS) $(OPTIMIZATIONS) -DDECODER_ONLY -g0 -Wall flif.cpp $(LDFLAGS) -L. -lflif_dec -o dflif
 
 # Decoder-only library - Apache2 (not built by default)
 libflif_dec$(LIBEXT): $(FILES_H) $(FILES_CPP) library/flif_dec.h library/flif-interface-private_dec.hpp library/flif-interface_dec.cpp
 	echo $(OS)
-	$(CXX) -std=gnu++11 $(CXXFLAGS) $(LIB_OPTIMIZATIONS) -DDECODER_ONLY -g0 -Wall -shared -fPIC $(FILES_CPP) library/flif-interface_dec.cpp $(LDFLAGS) -Wl,$(SONAME),libflif_dec$(LIBEXTV) -o libflif_dec$(LIBEXTV)
+	$(CXX) -std=gnu++11 $(CXXFLAGS) $(CPPFLAGS) $(LIB_OPTIMIZATIONS) -DDECODER_ONLY -g0 -Wall -shared -fPIC $(FILES_CPP) library/flif-interface_dec.cpp $(LDFLAGS) -Wl,$(SONAME),libflif_dec$(LIBEXTV) -o libflif_dec$(LIBEXTV)
 	ln -sf libflif_dec$(LIBEXTV) libflif_dec$(LIBEXT)
 
 # Decoder + encoder library - LGPL
@@ -71,7 +71,7 @@ viewflif: libflif$(LIBEXT) viewflif.c
 # The loader is LGPLed so there's no reason to use libflif_dec here
 # -Werror=implicit-function-declaration is useful here to check for preprocessor dependency errors
 libpixbufloader-flif$(LIBEXT): libflif$(LIBEXT) flif-pixbuf-loader.c
-	$(CC) -shared $(CFLAGS) -Ilibrary/ -fPIC -Wall -Werror=implicit-function-declaration $(shell pkg-config --cflags gdk-pixbuf-2.0) -o libpixbufloader-flif$(LIBEXT) flif-pixbuf-loader.c $(LDFLAGS) $(shell pkg-config --libs gdk-pixbuf-2.0) -L. -lflif
+	$(CC) -shared $(CFLAGS) $(CPPFLAGS) -Ilibrary/ -fPIC -Wall -Werror=implicit-function-declaration $(shell pkg-config --cflags gdk-pixbuf-2.0) -o libpixbufloader-flif$(LIBEXT) flif-pixbuf-loader.c $(LDFLAGS) $(shell pkg-config --libs gdk-pixbuf-2.0) -L. -lflif
 
 pixbufloader: libpixbufloader-flif$(LIBEXT)