-#define albe_v_calc(a,f,d) a->virial.xx+=f->x*d->x; \
- a->virial.yy+=f->y*d->y; \
- a->virial.zz+=f->z*d->z; \
- a->virial.xy+=f->x*d->y; \
- a->virial.xz+=f->x*d->z; \
- a->virial.yz+=f->y*d->z
+#define albe_v_calc(a,f,d) (a)->virial.xx+=(f)->x*(d)->x; \
+ (a)->virial.yy+=(f)->y*(d)->y; \
+ (a)->virial.zz+=(f)->z*(d)->z; \
+ (a)->virial.xy+=(f)->x*(d)->y; \
+ (a)->virial.xz+=(f)->x*(d)->z; \
+ (a)->virial.yz+=(f)->y*(d)->z