libdwarf: compile locally if not present

Change-Id: I70d1f653f4fc4ee4daeaa2c9c6bdbf1416e43c9b

CMakeLists.txt

@@ -4,7 +4,7 @@ if (NOT CMAKE_BUILD_TYPE)
 	set (CMAKE_BUILD_TYPE "Debug" CACHE STRING "Build type: Debug Release..." FORCE)
 endif (NOT CMAKE_BUILD_TYPE)
 
-enable_language(C ASM)
+enable_language(C ASM CXX)
 
 project(mckernel C ASM)
 set(MCKERNEL_VERSION "1.7.0")
@@ -34,6 +34,7 @@ include(GNUInstallDirs)
 include(CMakeParseArguments)
 include(Kbuild)
 include(CheckCCompilerFlag)
+include(AutoconfHelper)
 
 CHECK_C_COMPILER_FLAG(-Wno-implicit-fallthrough IMPLICIT_FALLTHROUGH)
 if(IMPLICIT_FALLTHROUGH)
@@ -135,6 +136,17 @@ if (NOT LIBIBERTY)
 	message(FATAL_ERROR "error: couldn't find libiberty")
 endif()
 
+# ignore libdwarf installed by libdwarf-devel-*.rpm because dwarf.h is located in /usr/include/libdwarf
+execute_process(COMMAND bash -c "[[ -f /usr/include/libdwarf/dwarf.h ]] && echo YES" OUTPUT_VARIABLE BAD_DWARF_H OUTPUT_STRIP_TRAILING_WHITESPACE)
+if (BAD_DWARF_H STREQUAL "YES")
+	message("WARNING: ignoring libdwarf installed by libdwarf-devel-*.rpm")
+else()
+	find_library(LIBDWARF dwarf)
+endif()
+if (NOT LIBDWARF)
+	message("WARNING: libdwarf will be compiled locally")
+endif()
+
 if (ENABLE_QLMPI)
 	find_package(MPI REQUIRED)
 endif()