[llvm] r190409 - Adding LZMA as dep for XML2 on 2.8.0 or higher

[Renato Golin]

Author: rengolin
Date: Tue Sep 10 09:24:17 2013
New Revision: 190409

URL: http://llvm.org/viewvc/llvm-project?rev=190409&view=rev
Log:
Adding LZMA as dep for XML2 on 2.8.0 or higher

LibXML2 config doesn't specify lzma as a dependency, which breaks
cross-compilation builds using new linkers (ld 2.21 or higher).

There is a bug on libxml2 to fix that, but since it's going to take
a while for things to go round and back, so we should have a harmless
addition of the library until then.

Modified:
    llvm/trunk/cmake/config-ix.cmake

Modified: llvm/trunk/cmake/config-ix.cmake
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/cmake/config-ix.cmake?rev=190409&r1=190408&r2=190409&view=diff
==============================================================================
--- llvm/trunk/cmake/config-ix.cmake (original)
+++ llvm/trunk/cmake/config-ix.cmake Tue Sep 10 09:24:17 2013
@@ -300,6 +300,20 @@ endif()
 find_package(LibXml2)
 if (LIBXML2_FOUND)
   set(CLANG_HAVE_LIBXML 1)
+  # When cross-compiling, liblzma is not detected as a dependency for libxml2,
+  # which makes linking c-index-test fail. But for native builds, all libraries
+  # are installed and checked by CMake before Makefiles are generated and everything
+  # works according to the plan. However, if a -llzma is added to native builds,
+  # an additional requirement on the static liblzma.a is required, but will not
+  # be checked by CMake, breaking native compilation.
+  # Since this is only pertinent to cross-compilations, and there's no way CMake
+  # can check for every foreign library on every OS, we add the dep and warn the dev.
+  if ( DEFINED CMAKE_CROSSCOMPILING )
+    if (NOT PC_LIBXML_VERSION VERSION_LESS "2.8.0")
+      message(STATUS "Adding LZMA as a dep to XML2 for cross-compilation, make sure liblzma.a is available.")
+      set(LIBXML2_LIBRARIES ${LIBXML2_LIBRARIES} "-llzma")
+    endif ()
+  endif ( CMAKE_CROSSCOMPILING )
 endif ()
 
 include(CheckCXXCompilerFlag)