This analysis of the error supersedes the above description. 

Please disregard all prior submitted files and work with this new EiffelBuild project and images.
The zip file contains the EiffelBuild project and the generated Eiffel application.

Steps in analysis:

1. Open the project CrashDebuggingPR#19562 by double clicking the bpr file.
2. You ought to observe a exception, matching "Uncaught Exception at start.png" with my trace in "Uncaught Exception at start.txt"
3. Ignore exception, presentation looks like "After ignoring exception before text change.png"
4. Using as sample first TEXT_FIELD "Mon" (Monday) as defined in "TEXT_FIELD Monday (heading).png"
5. I go and delete from the end n/o/M using the Back key. Then type X/X/X.
With each keypress there is an exception, the exceptions are copied over into file "exception trace while modyfing text.txt"
6. Result of field edit as in "TEXT_FIELD Monday (after).png"
7. Visual representation as in "After ignoring exception after text change.png"

and a generated Eiffel app compiled looks like "Application after Eiffel compilation.png"

Conclusion: EiffelBuild has a problem when modifying text with each keypress, and also when filling at start in from the project definition.

Note that this same error originally happened while editing the SPIN_BUTTON text property, as described intially. My guess is that this problem occurs with every widget that offers a text property (fixed once - fixed everywhere?).


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R.