Fix assume-filename handling in clang-format.el
Summary:
When 'buffer-file-name' is nil 'call-process-region' returned a segmentation fault error.
This was a problem when using clang-format-buffer on an orgmode source code editing buffer.
I fixed this problem by excluding the '-assume-filename' argument when 'buffer-file-name' is nil.
To make it a bit more flexible I also added an optional argument, 'assume-file-name', to specify an assume-filename that overrides 'buffer-file-name'.
Reviewers: klimek, djasper, phst, phi
Reviewed By: phst, phi
Subscribers: phi, jholewinski, mgorny, javed.absar, eraman, cfe-commits
Differential Revision: https://reviews.llvm.org/D37903
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@319621
91177308-0d34-0410-b5e6-
96231b3b80d8