Pass PRIVATE to target_link_libraries if using shared libraries.

A shared library (unlike a .a), has its dependencies recorded in the library and
we can pass PRIVATE to target_link_libraries.

This patch then removes some bogus dependencies when using
BUILD_SHARED_LIBS=ON. For example, we go from

build lib/CodeGen/CMakeFiles/LLVMCodeGen.dir/AggressiveAntiDepBreaker.cpp.o:
CXX_COMPILER /home/espindola/llvm/llvm/lib/CodeGen/AggressiveAntiDepBreaker.cpp
|| include/llvm/IR/intrinsics_gen lib/libLLVMSupport.so
lib/libLLVMCore.so lib/libLLVMBitReader.so
lib/libLLVMTransformUtils.so lib/libLLVMInstCombine.so
lib/libLLVMScalarOpts.so lib/libLLVMipa.so lib/libLLVMAnalysis.so
lib/libLLVMMCParser.so lib/libLLVMMC.so lib/libLLVMObject.so
lib/libLLVMTarget.so lib/libLLVMProfileData.so

to

build lib/CodeGen/CMakeFiles/LLVMCodeGen.dir/AggressiveAntiDepBreaker.cpp.o:
CXX_COMPILER /home/espindola/llvm/llvm/lib/CodeGen/AggressiveAntiDepBreaker.cpp
|| include/llvm/IR/intrinsics_gen lib/libLLVMSupport.so
lib/libLLVMCore.so lib/libLLVMTransformUtils.so
lib/libLLVMScalarOpts.so lib/libLLVMAnalysis.so lib/libLLVMMC.so
lib/libLLVMTarget.so

In fact, build.ninja goes from 5231028 bytes to 4896759 bytes.

With this, old verisons of bfd ld (2.24 is OK, 2.23 warns) will print a bogus
warning when building with BUILD_SHARED_LIBS.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221530 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 1 insertions, 15 deletions

diff --git a/cmake/modules/AddLLVM.cmake b/cmake/modules/AddLLVM.cmake
index 198393dc507..15ce6243ad5 100644
--- a/cmake/modules/AddLLVM.cmake
+++ b/cmake/modules/AddLLVM.cmake
@@ -359,22 +359,8 @@ function(llvm_add_library name)
       ${lib_deps}
       ${llvm_libs}
       )
-  elseif((CYGWIN OR WIN32) AND ARG_SHARED)
-    # Win32's import library may be unaware of its dependent libs.
-    target_link_libraries(${name} PRIVATE
-      ${ARG_LINK_LIBS}
-      ${lib_deps}
-      ${llvm_libs}
-      )
-  elseif(ARG_SHARED AND BUILD_SHARED_LIBS)
-    # FIXME: It may be PRIVATE since SO knows its dependent libs.
-    target_link_libraries(${name} PUBLIC
-      ${ARG_LINK_LIBS}
-      ${lib_deps}
-      ${llvm_libs}
-      )
   else()
-    # MODULE|SHARED
+    # We can use PRIVATE since SO knows its dependent libs.
     target_link_libraries(${name} PRIVATE
       ${ARG_LINK_LIBS}
       ${lib_deps}