Adding openmp project as a runtime project to projects/CMakeLists.txt

[jlpeyton]

Summary

We have just committed changes to our CMake system which makes it compatible for building as a project LLVM. The changes here simply add it as a runtime project which offers convenient CMake control variables for the user.

Chandler, I chose you as the reviewer because the CODE_OWNERS.txt file indicated you were the owner of the CMake build system.

[jlpeyton]

*Ping*

[chandlerc]

Cool!!!

I want to patch this locally and try it out, will review shortly.

[chandlerc]

So, looking at this, the openmp CMake isn't ready for prime time yet. It is using really weird conventions for variable naming (stuff like 'os', etc).

I think you'll need to make the openmp CMake look much more like libc++'s? That one has received some good attention recently and seems to integrate cleanly.

I don't think we can go forward here until that CMake is cleaned up.

[emaste]

It is using really weird conventions for variable naming (stuff like 'os', etc).

Yeah, I had a look at it for building on FreeBSD; it "just works" if I use CMake defaults, presumably because it sets os=lin which actually means "UNIX-like other than Apple." Later on there is a FREEBSD variable, but it doesn't seem to be used. I was going to take a look at fixing the FreeBSD cases, but will hold off while more fundamental rework is done.

projects/CMakeLists.txt

 # Discover the projects that use CMake in the subdirectories.
 # Note that explicit cmake invocation is required every time a new project is
 # added or removed.
 file(GLOB entries *)
 foreach(entry ${entries})
   if(IS_DIRECTORY ${entry} AND EXISTS ${entry}/CMakeLists.txt)
     if((NOT ${entry} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR}/compiler-rt) AND
        (NOT ${entry} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR}/dragonegg) AND
+       (NOT ${entry} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR}/openmp) AND
        (NOT ${entry} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR}/libcxx))
       add_subdirectory(${entry})
     endif()
   endif()
 endforeach(entry)
 
 # Also add in libc++ and compiler-rt trees if present (and we have
 # a sufficiently recent version of CMake where required).
 if(${LLVM_BUILD_RUNTIME})
   # MSVC isn't quite working with libc++ yet, disable it until issues are
   # fixed.
   if(NOT MSVC)
     add_llvm_external_project(libcxx)
   endif()
   if(NOT LLVM_BUILD_EXTERNAL_COMPILER_RT)
     add_llvm_external_project(compiler-rt)
   endif()
+  add_llvm_external_project(openmp)
 endif()
 
 add_llvm_external_project(dragonegg)