-Wno-deprecated-register with Clang

[Mike Alexander]

I just tried to compile GnuCash with clang and it failed because of the 
change in 4aed8b3 to not set -Wno-deprecated-register with clang.  The 
version of clang in Mavericks (MacOSX 10.9) certainly recognizes this 
parameter and won't compile GnuCash without it.  Which version of clang 
were you using which failed to recognize it?  I'm using "Apple LLVM 
version 5.1 (clang-503.0.40) (based on LLVM 3.4svn)".

Has anyone built GnuCash successfully with clang?  Even after I fixed 
that problem, I got lots of link errors that looked like a mismatched 
C++ library.  I haven't looked into this much yet, but it's probably 
because Mavericks replaced libstdc++ with libc++.  Since gcc works fine 
for me, it's not a high priority to fix this.

             Mike