Compiles but has dublicated definitions

Makefile

@@ -18,6 +18,9 @@ OBJS+= loader.o
 OBJS+= stack.o
 OBJS+= slots.o
 OBJS+= mps.o
+OBJS+= execute.o
+OBJS+= vm.o
+OBJS+= print.o
 
 all: main
 

alloc.c

@@ -0,0 +1,30 @@
+
+#include "alloc.h"
+
+// caller needs to make sure to root addr_o before calling this!
+// size is the size in bytes (including header)
+mps_res_t mps_alloc_obj(mps_addr_t *addr_o,
+                        mps_ap_t ap,
+                        uint32_t size,
+                        uint16_t cljtype,
+                        uint8_t mpstype) {
+    assert(addr_o != NULL);
+    assert(size > HEADER_SIZE);
+    mps_res_t res;
+
+    do {
+        res = mps_reserve(addr_o, ap, size);
+        if (res != MPS_RES_OK) return res;
+        struct obj_stub *obj = *addr_o;
+
+        obj->type = mpstype;
+        obj->cljtype = cljtype;
+        obj->size = size;
+
+        // zero all fields
+        memset(obj->ref, 0, size - HEADER_SIZE);
+
+    } while (!mps_commit(ap, *addr_o, size));
+
+    return res;
+}

alloc.h

@@ -0,0 +1,19 @@
+#ifndef _ALLOC_H_
+#define _ALLOC_H_
+
+struct obj_stub {
+    uint8_t type;
+    uint8_t _;
+    uint16_t cljtype;
+    uint32_t size; // incl. header
+    mps_addr_t ref[];
+} __attribute__((packed));
+
+
+mps_res_t mps_alloc_obj(mps_addr_t *addr_o,
+                        mps_ap_t ap,
+                        uint32_t size,
+                        uint16_t cljtype,
+                        uint8_t mpstype);
+
+#endif