[CMake] Check that compiler supports -fno-function-sections flag

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@200746 91177308-0d34-0410-b5e6-96231b3b80d8
tsan: add SANITIZER_INTERFACE_ATTRIBUTE to more callbacks
so that it's possible to override them from a dynamic library.



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@200747 91177308-0d34-0410-b5e6-96231b3b80d8