dynamic classes in the translation unit and check whether each one's key
function is defined when we got to the end of the TU (and when we got to the
end of each module). This is really terrible for modules performance, since it
causes unnecessary deserialization of every dynamic class in every compilation.
We now use a much simpler (and, in a modules build, vastly more efficient)
system: when we see an out-of-line definition of a virtual function, we check
whether that function was in fact its class's key function. (If so, we need to
emit the vtable.)
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@230830 91177308-0d34-0410-b5e6-96231b3b80d8
By C++ standard, the vtable should be generated if the first non-inline
virtual function is defined in the TU. Current version of clang doesn't
generate vtable if the first virtual function is defaulted, because the
key function is regarded as the defaulted function.
Patch by Li Kan!
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@161236 91177308-0d34-0410-b5e6-96231b3b80d8
Richard Smith