diff --git a/include/picrin/value.h b/include/picrin/value.h
index 1ca74b30..d72eb4f3 100644
--- a/include/picrin/value.h
+++ b/include/picrin/value.h
@@ -43,7 +43,7 @@ typedef struct {
 
 #define pic_ptr(v) ((void *)((long long)0xffffffffffff & (long long)(v).u.data))
 #define pic_vtype(v) (((v).u.type_ & 0xf0000)>>16)
-#define pic_init_value(v,vtype) (((v).u.type_ = ((unsigned int)0xfff00000|((vtype)<<16))), (v).u.i = 0)
+#define pic_init_value(v,vtype) (((v).u.type_ = ((unsigned int)0xfff00000|(unsigned int)((vtype)<<16))), (v).u.i = 0)
 
 #else
 
diff --git a/src/value.c b/src/value.c
index 2ea602bc..c63ff683 100644
--- a/src/value.c
+++ b/src/value.c
@@ -116,7 +116,6 @@ pic_false_value()
   pic_value v;
 
   pic_init_value(v, PIC_VTYPE_FALSE);
-  v.u.data = NULL;
   return v;
 }