// Copyright: (C) 2009 Gilles Muller, Julia Lawall, INRIA, DIKU. GPLv2. @def0@ expression x; position p0; @@ x@p0 = add_volume(...) @protected@ expression def0.x,E; position def0.p0; position p; statement S; @@ x@p0 ... when != x = E if (!IS_ERR(x) && ...) {<... x@p ...>} else S @unprotected@ expression def0.x,E; identifier fld; position def0.p0; position p != protected.p; @@ x@p0 ... when != x = E * x@p->fld