Revise comment and error message for the Bug 38 situation.  Also, make it print out the name of the function being used.
Revise comment and error message for the Bug 38 situation.  Also, make it
print out the name of the function being used.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@12347 91177308-0d34-0410-b5e6-96231b3b80d8

apple/swift-llvm,dslab-epfl/asap,GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,chubbymaggie/asap,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,chubbymaggie/asap,llvm-mirror/llvm,chubbymaggie/asap,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,dslab-epfl/asap,GPUOpen-Drivers/llvm,dslab-epfl/asap,llvm-mirror/llvm,chubbymaggie/asap,apple/swift-llvm,chubbymaggie/asap,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,dslab-epfl/asap,apple/swift-llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,dslab-epfl/asap,dslab-epfl/asap,chubbymaggie/asap,dslab-epfl/asap,GPUOpen-Drivers/llvm