diff options
Diffstat (limited to 'src/expr/expr_template.cpp')
| -rw-r--r-- | src/expr/expr_template.cpp | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/src/expr/expr_template.cpp b/src/expr/expr_template.cpp index f6d346630..51a734757 100644 --- a/src/expr/expr_template.cpp +++ b/src/expr/expr_template.cpp @@ -5,7 +5,7 @@ ** Major contributors: mdeters ** Minor contributors (to current version): taking, cconway ** This file is part of the CVC4 prototype. - ** Copyright (c) 2009, 2010 The Analysis of Computer Systems Group (ACSys) + ** Copyright (c) 2009, 2010, 2011 The Analysis of Computer Systems Group (ACSys) ** Courant Institute of Mathematical Sciences ** New York University ** See the file COPYING in the top-level source directory for licensing @@ -117,10 +117,24 @@ Expr& Expr::operator=(const Expr& e) { Assert(d_node != NULL, "Unexpected NULL expression pointer!"); Assert(e.d_node != NULL, "Unexpected NULL expression pointer!"); - ExprManagerScope ems(*this); - *d_node = *e.d_node; - d_exprManager = e.d_exprManager; + if(this != &e) { + if(d_exprManager == e.d_exprManager) { + ExprManagerScope ems(*this); + *d_node = *e.d_node; + } else { + // This happens more than you think---every time you set to or + // from the null Expr. It's tricky because each node manager + // must be in play at the right time. + + ExprManagerScope ems1(*this); + *d_node = Node::null(); + ExprManagerScope ems2(e); + *d_node = *e.d_node; + + d_exprManager = e.d_exprManager; + } + } return *this; } |