Allow the llvm bindings to be disabled

[v.g.vassilev]

Summary

There was some demand for this over the years, for example here.

My personal opinion is that bindings should be off by default because I doubt the majority of users need it.

This patch also helps a little when trying to fit the compilation of LLVM on the tight public infrastructures (such as travis).

[v.g.vassilev]

ping...

[pcc]

My personal opinion is that bindings should be off by default because I doubt the majority of users need it.

LLVM has plenty of features that the majority of users do not use. We still build and test them by default because we want to prevent developers from breaking them by accident. The same applies to the bindings. If a particular user has trouble with the bindings, they can always turn them off themselves.

[v.g.vassilev]

Reading back the patch, we are turning on the bindings by default ;)

[pcc]

Ah, LGTM then.

[v.g.vassilev]

r332816.

[sylvestre.ledru]

I took the liberty to add the option to the cmake doc
https://reviews.llvm.org/rL366204

[v.g.vassilev]

Thanks!

llvm/trunk/CMakeLists.txt

 option(LLVM_INCLUDE_TESTS "Generate build targets for the LLVM unit tests." ON)
 option(LLVM_INCLUDE_GO_TESTS "Include the Go bindings tests in test build targets." ON)
 
 option (LLVM_BUILD_DOCS "Build the llvm documentation." OFF)
 option (LLVM_INCLUDE_DOCS "Generate build targets for llvm documentation." ON)
 option (LLVM_ENABLE_DOXYGEN "Use doxygen to generate llvm API documentation." OFF)
 option (LLVM_ENABLE_SPHINX "Use Sphinx to generate llvm documentation." OFF)
 option (LLVM_ENABLE_OCAMLDOC "Build OCaml bindings documentation." ON)
+option (LLVM_ENABLE_BINDINGS "Build bindings." ON)
 
 set(LLVM_INSTALL_DOXYGEN_HTML_DIR "share/doc/llvm/doxygen-html"
     CACHE STRING "Doxygen-generated HTML documentation install directory")
 set(LLVM_INSTALL_OCAMLDOC_HTML_DIR "share/doc/llvm/ocaml-html"
     CACHE STRING "OCamldoc-generated HTML documentation install directory")
 
 option (LLVM_BUILD_EXTERNAL_COMPILER_RT
   "Build compiler-rt as an external project." OFF)

llvm/trunk/cmake/config-ix.cmake

if (LLVM_DOXYGEN_EXTERNAL_SEARCH)
       set(LLVM_DOXYGEN_SEARCH_MAPPINGS "" CACHE STRING "Doxygen Search Mappings")
     endif()
   endif()
 else()
   message(STATUS "Doxygen disabled.")
 endif()
 
 set(LLVM_BINDINGS "")
-if(WIN32)
+find_program(GO_EXECUTABLE NAMES go DOC "go executable")
+if(WIN32 OR NOT LLVM_ENABLE_BINDINGS)
   message(STATUS "Go bindings disabled.")
 else()
-  find_program(GO_EXECUTABLE NAMES go DOC "go executable")
   if(GO_EXECUTABLE STREQUAL "GO_EXECUTABLE-NOTFOUND")
     message(STATUS "Go bindings disabled.")
   else()
     execute_process(COMMAND ${GO_EXECUTABLE} run ${PROJECT_SOURCE_DIR}/bindings/go/conftest.go
                     RESULT_VARIABLE GO_CONFTEST)
     if(GO_CONFTEST STREQUAL "0")
       set(LLVM_BINDINGS "${LLVM_BINDINGS} go")
       message(STATUS "Go bindings enabled.")
if(LD64_EXECUTABLE)
     set(LD64_EXECUTABLE ${LD64_EXECUTABLE} CACHE PATH "ld64 executable")
     message(STATUS "Found ld64 - ${LD64_EXECUTABLE}")
   endif()
 endif()
 
 # Keep the version requirements in sync with bindings/ocaml/README.txt.
 include(FindOCaml)
 include(AddOCaml)
-if(WIN32)
+if(WIN32 OR NOT LLVM_ENABLE_BINDINGS)
   message(STATUS "OCaml bindings disabled.")
 else()
   find_package(OCaml)
   if( NOT OCAML_FOUND )
     message(STATUS "OCaml bindings disabled.")
   else()
     if( OCAML_VERSION VERSION_LESS "4.00.0" )
       message(STATUS "OCaml bindings disabled, need OCaml >=4.00.0.")