Patch to Communist Dogifesto to make it build on linux

linux-dogifesto.txt

diff --git a/Makefile b/Makefile
index 8c4abfb..71ee675 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,10 @@ CFLAGS_DEBUG := -Wall -g -O0 -std=c11
 CFLAGS_RELEASE := -Wall -g -O3 -flto -std=c11
 INCLUDES := -Isrc
 # On Linux, only static link with my custom libcurl
-LIBS_LINUX := -l:src/libs/linux/GL/libGLEW.a \
+
+GLEWLIBS:=$(shell pkg-config --libs-only-l glew)
+
+LIBS_LINUX := ${GLEWLIBS} \
  -lSDL2 -lGL -lm
 # On Windows, static link with custom libcurl, GLEW, and SDL2
 LIBS_WIN32 := -lmingw32 \
@@ -69,7 +72,10 @@ release_win64: CFLAGS := $(CFLAGS_RELEASE) -Wl,--export-all-symbols -mwindows \
 release_win64: TARGET := $(TARGET).exe
 release_win64: clean dump_shaders procgame
 
-procgame: obj/main.o
+obj:
+	mkdir obj
+
+procgame: obj/main.o obj
 	$(CC) $(CFLAGS) -o $(TARGET) obj/main.o $(GAME) $(PROCGL) $(PROCGL_LIBS) $(LIBS)
 
 obj/main.o: src/main.c $(GAME) $(PROCGL) $(PROCGL_LIBS)
@@ -212,11 +218,12 @@ obj/wave.o: src/procgl/wave.c src/procgl/wave.h
 obj/audio.o: src/procgl/audio.c src/procgl/audio.h \
  src/procgl/wave.h src/procgl/arr.h src/procgl/ext/wavfile.h
 	$(CC) $(CFLAGS) -o obj/audio.o -c src/procgl/audio.c $(INCLUDES)
-obj/sdf.o: src/procgl/sdf.c src/procgl/sdf.h \
- src/procgl/wave.h src/procgl/arr.h
+src/procgl/sdf_keywords.gperf.c:	src/procgl/sdf_keywords.gperf
 	gperf src/procgl/sdf_keywords.gperf \
         -H pg_sdf_keyword_hash -N pg_sdf_keyword_read -t --omit-struct-type \
         > src/procgl/sdf_keywords.gperf.c &
+obj/sdf.o: src/procgl/sdf.c src/procgl/sdf.h \
+ src/procgl/wave.h src/procgl/arr.h src/procgl/sdf_keywords.gperf.c
 	$(CC) $(CFLAGS) -o obj/sdf.o -c src/procgl/sdf.c $(INCLUDES)
 obj/sdf_functions.o: src/procgl/sdf_functions.c src/procgl/sdf.h \
  src/procgl/wave.h src/procgl/arr.h
@@ -264,4 +271,5 @@ dump_shaders: src/procgl/shaders/*.glsl
 clean:
 	rm -f obj/*.o
 	rm -f src/procgl/shaders/*.glsl.h
+	rm -f src/procgl/sdf_keywords.gperf.c