Added debug and release builds

Makefile

 CC       = gcc
-CFLAGS   = -O3 -march=native
-CPPFLAGS = -Iinclude/ -Ilib/sais-lite-lcp/ -DNDEBUG -Wall -Wextra -pedantic
+CFLAGS   = -march=native
+CPPFLAGS = -Iinclude/ -Ilib/sais-lite-lcp/ -Wall -Wextra -pedantic
+DEBUG    = -O0 -ggdb3
+RELEASE  = -O3 -DNDEBUG
 SOURCES  = $(shell find src/ -name '*.c')
 OBJECTS  = $(SOURCES:.c=.o)
 DEPS     = $(OBJECTS:.o=.d)
 LIBS     = $(shell find lib/ -name '*.a')
+TARGET   = libgesa.a
 
-.PHONY: clean tests
+.PHONY: all debug clean release tests
 
-libgesa.a: $(LIBS) $(OBJECTS)
+all: debug
+
+debug: CFLAGS += $(DEBUG)
+debug: $(TARGET)
+
+release: CFLAGS += $(RELEASE)
+release: $(TARGET)
+
+$(TARGET): $(LIBS) $(OBJECTS)
 	$(MAKE) -wC lib/
 	ar rcsT $@ $(LIBS) $(OBJECTS)
 
-tests: libgesa.a
+tests: $(TARGET)
 	$(MAKE) -wC tests/
 
 clean:
-	rm -f $(OBJECTS) $(DEPS) libgesa.a
+	rm -f $(OBJECTS) $(DEPS) $(TARGET)
 
 -include $(DEPS)
 

include/gesa.h

@@ -33,7 +33,7 @@ typedef struct
 } GESA; // GESA
 
 
-// Creates a GESA from a single string
+// Creates a GESA from a single string that *must* be '\0' terminated
 // On success it returns 0
 int GESA_create(GESA* const              gesa,
                 GESA_char_t const* const string,