Simplify build system

RELEASE and DEBUG builds have differing build flags, triggered by
setting RELEASE variable.  No longer doing object based compilation
because:
+ gcc is fast enough without it
+ stale code compilation bugs are annoying
+ having one output binary to clean-up is just easier when switching
build-types

Makefile

@@ -1,20 +1,28 @@
 CC=gcc
-CFLAGS=-Wall -Wextra -Wpedantic -ggdb -fsanitize=address -std=c11
-LIBS=
-OBJECTS=lib.o parser.o main.o
 OUT=obf.out
+LIBS=
 ARGS=
 
-%.o: %.c
-	$(CC) $(CFLAGS) -c $^ -o $@ $(LIBS)
+RELEASE=0
+GFLAGS=-Wall -Wextra -Werror -Wswitch-enum -std=c11
+DFLAGS=-ggdb -fsanitize=address -fsanitize=undefined -DDEBUG
+RFLAGS=-O3
+ifeq ($(RELEASE), 1)
+CFLAGS=$(GFLAGS) $(RFLAGS)
+else
+CFLAGS=$(GFLAGS) $(DFLAGS)
+endif
 
-$(OUT): $(OBJECTS)
+.PHONY: all
+all: $(OUT)
+
+$(OUT): lib.c parser.c main.c
 	$(CC) $(CFLAGS) $^ -o $@ $(LIBS)
 
-.PHONY:
-clean:
-	rm -rfv $(OUT) $(OBJECTS)
-
 .PHONY: run
 run: $(OUT)
 	./$^ $(ARGS)
+
+.PHONY:
+clean:
+	rm -v $(OUT)

main.c

@@ -15,7 +15,6 @@
 
 #define MEMORY_DEFAULT 30000
 
-#define DEBUG        0
 #define MIN_MEM_DUMP 64
 
 typedef struct
@@ -23,7 +22,7 @@ typedef struct
   size_t dp;
   uint8_t memory[MEMORY_DEFAULT];
 
-#if DEBUG
+#ifdef DEBUG
   size_t dp_max;
 #endif
 } machine_t;
@@ -62,13 +61,13 @@ void interpret(machine_t *cpu, node_t *ast, size_t num)
         i = node.loop_ref;
       break;
     }
-#if DEBUG
+#ifdef DEBUG
     if (cpu->dp > cpu->dp_max)
       cpu->dp_max = cpu->dp + 1;
 #endif
   }
 
-#if DEBUG
+#ifdef DEBUG
   if (cpu->dp_max < MIN_MEM_DUMP)
     cpu->dp_max = MIN_MEM_DUMP;
 #endif
@@ -90,9 +89,9 @@ int main(int argc, char *argv[])
     return 1;
   }
 
-  char *filepath, *file_data;
-  buffer_t *buffer;
-  struct PResult res;
+  char *filepath = NULL, *file_data = NULL;
+  buffer_t *buffer   = NULL;
+  struct PResult res = {0};
 
   machine_t machine = {0};
 
@@ -101,7 +100,7 @@ int main(int argc, char *argv[])
     filepath = argv[i];
 
     FILE *handle = fopen(filepath, "r");
-#if DEBUG
+#ifdef DEBUG
     printf("[DEBUG]: Attempting to open file handle to %s\n", filepath);
 #endif
     if (!handle)
@@ -111,12 +110,12 @@ int main(int argc, char *argv[])
     }
     file_data = fread_all(handle);
     fclose(handle);
-#if DEBUG
+#ifdef DEBUG
     printf("[DEBUG]: Read data from file %s\n", filepath);
 #endif
 
     buffer = buffer_init_str(filepath, file_data, strlen(file_data));
-#if DEBUG
+#ifdef DEBUG
     puts("[DEBUG]: Initialised buffer");
 #endif
     res = parse_buffer(buffer);
@@ -126,7 +125,7 @@ int main(int argc, char *argv[])
       goto error;
     }
 
-#if DEBUG
+#ifdef DEBUG
     char *str = ast_to_str(res.nodes, res.size);
     printf("[DEBUG]: Parsed buffer (%lu nodes parsed)\n\t[DEBUG]: Out=%s\n",
            res.size, str);
@@ -135,7 +134,7 @@ int main(int argc, char *argv[])
 
     interpret(&machine, res.nodes, res.size);
 
-#if DEBUG
+#ifdef DEBUG
     printf("[DEBUG]: Finished interpreting, memory:");
     for (size_t i = 0; i < machine.dp_max; ++i)
     {