[llvm-commits] PATCH: (cmake) Fix tool-less build

[Óscar Fuentes]

With a LLVM checkout, without other projects in LLVM's source tree
(Clang...), configure with

          
mkdir foo
cd foo
cmake -DLLVM_BUILD_TOOLS=OFF ../llvm

or, if Clang is under tools/ subdirectory:

cmake -DLLVM_BUILD_TOOLS=OFF -DLLVM_EXTERNAL_CLANG_BUILD=OFF ../llvm

(BTW, shouldn't it be LLVM_BUILD_EXTERNAL_CLANG, for consistency with
LLVM_BUILD_(TOOLS|EXAMPLES|etc) ?)

This fails with

CMake Error at cmake/modules/AddLLVM.cmake:280 (add_dependencies):
  add_dependencies called with incorrect number of arguments
Call Stack (most recent call first):
  CMakeLists.txt:441 (add_lit_target)


Apparently, ARG_DEPENDS is empty if there are no tools nor clang in the
build. The patch below fixes the problem. A possible problem happens
when the user builds with the above mentioned options, then builds the
tools or clang with its own `make' command (because the options just
remove those targets from the default build.)


diff --git a/cmake/modules/AddLLVM.cmake b/cmake/modules/AddLLVM.cmake
index 43ee9a0..7e1f704 100755
--- a/cmake/modules/AddLLVM.cmake
+++ b/cmake/modules/AddLLVM.cmake
@@ -277,7 +277,9 @@ function(add_lit_target target comment)
     COMMAND ${LIT_COMMAND} ${ARG_DEFAULT_ARGS}
     COMMENT "${comment}"
     )
-  add_dependencies(${target} ${ARG_DEPENDS})
+  if( ARG_DEPENDS )
+    add_dependencies(${target} ${ARG_DEPENDS})
+  endif()
 endfunction()
 
 # A function to add a set of lit test suites to be driven through 'check-*' targets.