Long, long ago I hit what presumably was a compiler bug in Visual Basic. Ran perfectly in the IDE, data corruption when compiled to disk. (I didn't have the e

Long, long ago I hit what presumably was a compiler bug in Visual Basic. Ran perfectly in the IDE, data corruption when compiled to disk. (I didn't have the experience to pin it down well back then.) Forget this, stay with the previous version. I've also had a library + debugger bug that really left me pulling my hair out. Delphi, protected mode, the library dealing with real mode data. Running the code it would normally segment fault but occasionally work correctly. Single-stepping in the debugger would work correctly 100% of the time. The library turned out to be riddled with the bug, they were using pointers to point to the real mode addresses. The mere act of loading an invalid pointer is a segment fault and the code emitted by the compiler would copy the pointers by loading them. Note that they were not being followed, if they pointed to nonsense it didn't matter, but if it wasn't a valid address, boom. Somehow the debugger was successfully executing the invalid load when single stepping. I never investigated exactly what it was up to, I figure it might have been simulating the command to avoid having to write a breakpoint into memory that conceivably could have been read only.