diff -r 56cd8111b7f7 -r 41300fa6a67c src/corelib/io/qprocess.cpp
--- a/src/corelib/io/qprocess.cpp	Tue Jan 26 12:42:25 2010 +0200
+++ b/src/corelib/io/qprocess.cpp	Tue Feb 02 00:43:10 2010 +0200
@@ -275,7 +275,7 @@
 */
 bool QProcessEnvironment::operator==(const QProcessEnvironment &other) const
 {
-    return d->hash == other.d->hash;
+    return d == other.d || (d && other.d && d->hash == other.d->hash);
 }
 
 /*!
@@ -334,6 +334,7 @@
 */
 void QProcessEnvironment::insert(const QString &name, const QString &value)
 {
+    // d detaches from null
     d->hash.insert(prepareName(name), prepareValue(value));
 }