[LTO] Fix a use-after-free introduced in r278907 and caught by ASan.

The ASan build bot caught this right away:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/15580/steps/check-llvm%20asan/logs/stdio

This was also breaking a Windows build bot I'm pretty sure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278912 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed