LLVMTargetMachine.cpp assert not fully descriptive

[llvmbot]

Bugzilla Link	11217
Resolution	FIXED
Resolved on	Oct 25, 2011 15:42
Version	trunk
OS	Windows NT
Blocks	#11571
Reporter	LLVM Bugzilla Contributor

Extended Description

LLVMTargetMachine.cpp says:
// TargetSelect.h moved to a different directory between LLVM 2.9 and 3.0,
// and if the old one gets included then MCAsmInfo will be NULL and
// we'll crash later.
// Provide the user with a useful error message about what's wrong.
assert(AsmInfo && "MCAsmInfo not initialized."
"Make sure you include the correct TargetSelect.h!");

This can also occur if you fail to do llvm::InitializeAllTargetMCs(), which is new (to me anyway). Found this upgrading my code from 2.9-ish SVN to 3.0-ish SVN.

It would be good if the assert mentioned this other possibility.

[llvmbot]

Fixed in r142956. Now also mentions, "and that InitializeAllTargetMCs() is being invoked!"

Bill, I don't think this is absolutely necessary to pull in for the release, but on the other hand, it's very low risk since it's just changing the message text on an assert().

[llvmbot]

I added it since it's listed as a blocker. It's a "nice to have" and like you say low-risk.