Module dtor segfaults on empty PHI nodes.

[llvmbot]

Bugzilla Link	2460
Resolution	FIXED
Resolved on	Jun 15, 2008 23:03
Version	trunk
OS	Linux
Attachments	reproduces the bug
Reporter	LLVM Bugzilla Contributor

Extended Description

If a module has an empty PHI node (a PHI node on which addIncomingBlock() has not been called), then it segfaults while the module object is destroyed. It can be reproduced by the attached test program.

Probably can be fixed by modifying User::dropHungoffUses().

[lattner]

Fixed:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20080609/063668.html