We drop the -g for debug output but we keep the -O0, as we don't want GCC
to optimize out some critical math.

--- a/Makefile
+++ b/Makefile
@@ -1,13 +1,13 @@
-CFLAGS=-Wextra -Wall -O0 -g -pipe `pkg-config --cflags alsa`
-LIBS=`pkg-config --libs alsa` -lm
+CFLAGS+=-Wextra -Wall -O0 $(shell $(PKG_CONFIG) --cflags alsa)
+LIBS=-lm $(shell $(PKG_CONFIG) --libs alsa)
 
 all: dbmeasure dbverify
 
 dbmeasure: dbmeasure.o
-	$(CC) -o dbmeasure $^ $(CFLAGS) $(LIBS)
+	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) -o dbmeasure $^ $(LIBS)
 
 dbverify: dbverify.o
-	$(CC) -o dbverify $^ $(CFLAGS) $(LIBS)
+	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) -o dbverify $^ $(LIBS)
 
 clean:
 	rm -f *.o dbmeasure dbverify