Version:           1.2.92 (using KDE 3.2.3, compiled sources)
Compiler:          gcc version 3.3.3
OS:                Linux (i686) release 2.4.26

Ok, what can I tell you about this bug... Try loading the attached file (on startup) and Umbrello will crash. Valgrind says (with Umbrello output between):

umbrello: Looking up generator for language XMLSchema
umbrello:  A new uni-association has been created.
umbrello: UMLWidget::loadFromXMI(id=10): m_pObject is already set (new_class)
umbrello: UMLWidget::loadFromXMI(id=11): m_pObject is already set (new_class_1)
umbrello: WARNING: Show Event for class diagram
umbrello: AssociationWidget::widgetMoved() called during load of XMI
umbrello: AssociationWidget::widgetMoved() called during load of XMI
umbrello: AssociationWidget::widgetMoved() called during load of XMI
umbrello: AssociationWidget::widgetMoved() called during load of XMI
umbrello: CodeGeneratorFactory created
umbrello: Looking up generator for language Cpp
umbrello: WARNING:  loadFromXMI: missing code document w/ id:2, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:3, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:4, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:5, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:6, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:7, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:8, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:9, plowing ahead with pre-generated one.
umbrello: ERROR: Failed to find codeclassfield for parent uml id:12 (role id:1) Do you have a corrupt classifier code document?
umbrello: ERROR:  LoadFromXMI: can't load classfield parent_id:12 do you have a corrupt savefile?
==3538==
==3538== Invalid read of size 4
==3538==    at 0x3D430D7B: __dynamic_cast (in /usr/lib/libstdc++.so.5.0.6)
==3538==    by 0x81196F1: CodeGenObjectWithTextBlocks::findParentObjectForTaggedTextBlock(QString const&) (codegenobjectwithtextblocks.cpp:175)
==3538==    by 0x8119153: CodeGenObjectWithTextBlocks::addTextBlock(TextBlock*) (codegenobjectwithtextblocks.cpp:86)
==3538==    by 0x811A904: CodeGenObjectWithTextBlocks::loadChildTextBlocksFromNode(QDomElement&) (codegenobjectwithtextblocks.cpp:473)
==3538==  Address 0x3DAAA2FC is 0 bytes inside a block of size 76 free'd
==3538==    at 0x3C01D9C5: operator delete(void*) (vg_replace_malloc.c:129)
==3538==    by 0x811A29F: CodeGenObjectWithTextBlocks::loadChildTextBlocksFromNode(QDomElement&) (codegenobjectwithtextblocks.cpp:479)
==3538==    by 0x8119F4B: CodeGenObjectWithTextBlocks::setAttributesFromNode(QDomElement&) (codegenobjectwithtextblocks.cpp:386)
==3538==    by 0x8111EB6: CodeDocument::setAttributesFromNode(QDomElement&) (codedocument.cpp:434)
umbrello: ERROR: Failed to find codeclassfield for parent uml id:12 (role id:0) Do you have a corrupt classifier code document?
umbrello: ERROR:  LoadFromXMI: can't load classfield parent_id:12 do you have a corrupt savefile?
umbrello: WARNING:  loadFromXMI: missing code document w/ id:cppheader2, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:cppheader3, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:cppheader4, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:cppheader5, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:cppheader6, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:cppheader7, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:cppheader8, plowing ahead with pre-generated one.
umbrello: WARNING:  loadFromXMI: missing code document w/ id:cppheader9, plowing ahead with pre-generated one.
umbrello: ERROR: Failed to find codeclassfield for parent uml id:12 (role id:1) Do you have a corrupt classifier code document?
umbrello: ERROR:  LoadFromXMI: can't load classfield parent_id:12 do you have a corrupt savefile?
==3538==
==3538== Invalid read of size 4
==3538==    at 0x3D430D7B: __dynamic_cast (in /usr/lib/libstdc++.so.5.0.6)
==3538==    by 0x81196F1: CodeGenObjectWithTextBlocks::findParentObjectForTaggedTextBlock(QString const&) (codegenobjectwithtextblocks.cpp:175)
==3538==    by 0x8119153: CodeGenObjectWithTextBlocks::addTextBlock(TextBlock*) (codegenobjectwithtextblocks.cpp:86)
==3538==    by 0x8262FC1: CPPHeaderCodeDocument::loadChildTextBlocksFromNode(QDomElement&) (cppheadercodedocument.cpp:147)
==3538==  Address 0x3DFF38A8 is 0 bytes inside a block of size 76 free'd
==3538==    at 0x3C01D9C5: operator delete(void*) (vg_replace_malloc.c:129)
==3538==    by 0x8262B1F: CPPHeaderCodeDocument::loadChildTextBlocksFromNode(QDomElement&) (cppheadercodedocument.cpp:206)
==3538==    by 0x8119F4B: CodeGenObjectWithTextBlocks::setAttributesFromNode(QDomElement&) (codegenobjectwithtextblocks.cpp:386)
==3538==    by 0x8111EB6: CodeDocument::setAttributesFromNode(QDomElement&) (codedocument.cpp:434)
==3538==
==3538== Invalid read of size 4
==3538==    at 0x3D430D7B: __dynamic_cast (in /usr/lib/libstdc++.so.5.0.6)
==3538==    by 0x81196F1: CodeGenObjectWithTextBlocks::findParentObjectForTaggedTextBlock(QString const&) (codegenobjectwithtextblocks.cpp:175)
==3538==    by 0x8119153: CodeGenObjectWithTextBlocks::addTextBlock(TextBlock*) (codegenobjectwithtextblocks.cpp:86)
==3538==    by 0x812ACF8: HierarchicalCodeBlock::addTextBlock(TextBlock*) (hierarchicalcodeblock.cpp:126)

Well, the interesting is, that the problem happens in ClassifierCodeDocument::findCodeClassFieldFromParentID; This function checks first, if to search attribute-based or association(role)-based. role_id==-1, so association(role)-based wins. But the loop is never entered, because at this moment the m_classfieldVector is still empty. So that's where the problem starts...

Ok, we also have a backtrace:

Program received signal SIGSEGV, Segmentation fault.
0x41421d7f in __dynamic_cast () from /usr/lib/./libstdc++.so.5
(gdb) bt
#0  0x41421d7f in __dynamic_cast () from /usr/lib/./libstdc++.so.5
#1  0x08119a82 in CodeGenObjectWithTextBlocks::findParentObjectForTaggedTextBlock (this=0x84b73a8, tag=@0xbfffeca0) at codegenobjectwithtextblocks.cpp:175
#2  0x081194e4 in CodeGenObjectWithTextBlocks::addTextBlock (this=0x84b73a8,
    add_object=0x84bade0) at codegenobjectwithtextblocks.cpp:86
#3  0x0811ac95 in CodeGenObjectWithTextBlocks::loadChildTextBlocksFromNode (
    this=0x84b73a8, root=@0x6f0043) at codegenobjectwithtextblocks.cpp:473
#4  0x0811a2dc in CodeGenObjectWithTextBlocks::setAttributesFromNode (
    this=0x84b73a8, root=@0xbffff0d0) at codegenobjectwithtextblocks.cpp:386
#5  0x08112247 in CodeDocument::setAttributesFromNode (this=0x84b7380,
    root=@0xbffff0d0) at codedocument.cpp:434
#6  0x08103be3 in ClassifierCodeDocument::setAttributesFromNode (
    this=0x84b7380, elem=@0xbffff0d0) at classifiercodedocument.cpp:552
#7  0x081049e6 in ClassifierCodeDocument::loadFromXMI (this=0x6f0043,
    root=@0xbffff0d0) at classifiercodedocument.cpp:639
#8  0x08115cf8 in CodeGenerator::loadFromXMI (this=0x840dcc8,
    qElement=@0xbffff1a0) at codegenerator.cpp:230
#9  0x0815d8a6 in UMLApp::createGenerator (this=0x83e28d8) at uml.cpp:1177
#10 0x0815ee69 in UMLApp::initSavedCodeGenerators (this=0x83e28d8)
    at uml.cpp:1441
#11 0x08159863 in UMLApp::openDocumentFile (this=0x83e28d8, url=@0x1)
    at uml.cpp:412
#12 0x0813e709 in main (argc=1, argv=0xbffff474) at main.cpp:77

But I don't think it is really interesting. Hope someone knowing the complete loading stuff can fix this... Please also keep in mind, that maybe the xmi file is corrupted. Then there is a problem during saving. You can recreate the file with the following steps:

1. create 2 classes
2. add an association to between the classes
3. set role names and multiplicity to this association
4. save file
5. close Umbrello and restart -> Crash