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git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@29056 a592a061-630c-0410-9148-cb99ea01b6c8

diff --git a/src/Buffer.cpp b/src/Buffer.cpp
index e0998f8330b8f7884268e6ee5a41e5c9e2ffb594..888f82072882f8237aada52558df3516180e92a9 100644 (file)
--- a/src/Buffer.cpp
+++ b/src/Buffer.cpp
@@ -228,6 +228,9 @@ public:
        /// This is here to force the test to be done whenever parent_buffer
        /// is accessed.
        Buffer const * parent() const { 
+               // if parent_buffer is not loaded, then it has been unloaded,
+               // which means that parent_buffer is an invalid pointer. So we
+               // set it to null in that case.
                if (!theBufferList().isLoaded(parent_buffer))
                        parent_buffer = 0;
                return parent_buffer;