Yet Another MFC Bug

[billroper]

This is cute. In Visual Studio 2005, if you use CString::FormatMessage() in a way that generates an empty string, it throws a CMemoryException indicating that you're out of memory. Hilarity ensues.

What you should get is a nice harmless null-terminated empty string.

And maybe you do in Visual Studio 2008. But I'm not holding my breath.

Comments

[scs-11.livejournal.com]

I will refrain from my usual MS-bashing, but lordy, how in the world did that not get caught in testing?

[billroper]

Because someone missed testing for an edge case. I'm sure that the first thought that the developer had upon seeing my bug was "Why would someone want to do that?"

This is why I acknowledged in the bug report that it certainly seemed like a strange thing to do, but that since the format string and the argument had been selected from variables, it wasn't something that was particularly easy for me to detect and prevent.