Compile error: 'os-fence.h' file not found

In file included from /home/constantine/llvm/projects/compiler-rt/lib/cilk/runtime/cilk-abi.c:54:
/home/constantine/llvm/projects/compiler-rt/lib/cilk/runtime/os.h:152:10: fatal error: 'os-fence.h' file not found
#include "os-fence.h"
         ^
1 error generated.
[1768/1811] Building CXX object tools/...es/libclang.dir/CXSourceLocation.cpp.o
ninja: build stopped: subcommand failed.

As a temporary hardcoded solution that works for me so far: https://github.com/procedural/compiler-rt/commit/885fbcab4d1fc33c7e2240a25be8aa1298574393

[georgefx]

@procedural Thanks for the fix, affects me too.