This reverts r348083. This was based on a misreading of the spec
for printf specifiers.
Also revert r343653, as without a subsequent patch, a correctly
specified format for a vector will incorrectly warn.
Fixes bug 40491.
llvm-svn: 352539
The spec is ambiguous on whether vector types are allowed to be
implicitly converted. The only legal context I think this can
be used for OpenCL is printf, where it seems necessary.
llvm-svn: 348083