hack which introduces some strange inconsistencies in compatibility
for block pointers.
Note that unlike an earlier revision proposed on cfe-commits, this patch
still allows declaring block pointers without a prototype.
llvm-svn: 73041
specific targets default them to on. Default blocks to on on 10.6 and later.
Add a -fblocks option that allows the user to override the target's default.
Use -fblocks in the various testcases that use blocks.
llvm-svn: 60563
Eli Friedman