[cmake] Fix builds with LLVM_ENABLE_PIC=0

[labath]

Summary

When this flag is specified, the target llvm-lto is not built, but is still
used as a dependency of the test targets. cmake 2.8 silently ignored this
situation, but with cmake_minimum_required(3.4) it becomes an error. Fix this
by avoiding the inclusion the target as a dependency.

[beanz]

LGTM.

[chapuni]

Have you tested if it might work? In fact, it didn't work.

cfe/trunk/test/CMakeLists.txt

78

llvm-lto was not processed before clang. Fixed in r271585.

83

It would be redundant unless libLTO.so were actually used in tests.

cfe/trunk/test/CMakeLists.txt

set(CLANG_TEST_PARAMS
   )
 
 if( NOT CLANG_BUILT_STANDALONE )
   list(APPEND CLANG_TEST_DEPS
     llvm-config
     FileCheck count not
     llc
     llvm-bcanalyzer
-    llvm-lto
     llvm-objdump
     llvm-profdata
     llvm-readobj
     llvm-symbolizer
-    LTO
     opt
     )
+
+  if(TARGET llvm-lto)
+    set(LLVM_TEST_DEPENDS ${LLVM_TEST_DEPENDS} llvm-lto)
+  endif()
+
+  if(TARGET LTO)
+    set(LLVM_TEST_DEPENDS ${LLVM_TEST_DEPENDS} LTO)
+  endif()
 endif()
 
 add_custom_target(clang-test-depends DEPENDS ${CLANG_TEST_DEPS})
 set_target_properties(clang-test-depends PROPERTIES FOLDER "Clang tests")
 
 add_lit_testsuite(check-clang "Running the Clang regression tests"
   ${CMAKE_CURRENT_BINARY_DIR}
   #LIT ${LLVM_LIT}