llvm dev - Mar 2011 - [LLVMdev] make: *** No rule to make target `/Makefile', needed by `Makefile'. Stop.

I have two different machines with LLVM source trees on them.
One builds fine, the other gives the error above.

This behavior started on Tuesday.
Both machines have the sources on a non-boot disk.

The source trees are identical, and in both cases, I have a separate object
directory.
I have removed the object directories, and reran configure:
	mkdir llvm-build
	cd llvm-build
	../llvm/configure

Still get the same behavior (success on one, failure on the other).

$ make -v
> GNU Make 3.81
> Copyright (C) 2006  Free Software Foundation, Inc.
> This is free software; see the source for copying conditions.
> There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
> PARTICULAR PURPOSE.
> 
> This program built for i386-apple-darwin10.0

The only differences that I can think of are:
1) The unsuccessful machine has recently had XCode 4 installed.
2) The successful machine has the sources on a volume with a case-sensitive file
system.

Any ideas?

-- Marshall

Marshall Clow     Idio Software   <mailto:mclow.lists at gmail.com>

A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly
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