cmake: find libiberty headers via cmake module

The libiberty headers moved from /usr/include (and a part of binutils-dev)
to /usr/include/libiberty (libiberty-dev) between Ubuntu 13.10 and 14.04,
which made a proper cmake search module necessary.  Searching still
continues working well on Debian 7.

Change-Id: I324e5ccb847e4664442d6fa7d7a027705a4f0587

cmake/FindLibIberty.cmake

@@ -0,0 +1,42 @@
+# - FindLibIberty.cmake
+# This module can find libiberty on both Debian 7 and Ubuntu 14.04
+# (The libiberty headers moved from /usr/include to /usr/include/libiberty
+# between Ubuntu 13.10 and 14.04, which made this search module necessary.)
+#
+# The following variables will be defined for your use:
+#
+#   LibIberty_FOUND - TRUE if both library and headers were found
+#   LibIberty_INCLUDE_DIRS - Include directories
+#   LibIberty_LIBRARIES - Library path
+
+# set(LibIberty_PREFER_DYNAMIC True) if you want to prefer the dynamic library
+
+if(LibIberty_PREFER_DYNAMIC)
+	set(LibIberty_SEARCHORDER libiberty.so libiberty.a)
+else()
+	set(LibIberty_SEARCHORDER libiberty.a libiberty.so)
+endif()
+
+find_library(LibIberty_LIBRARIES NAMES ${LibIberty_SEARCHORDER})
+
+find_path(LibIberty_INCLUDE_DIRS libiberty.h
+	PATHS
+		/usr/include /usr/include/libiberty
+		/usr/local/include /usr/local/include/libiberty
+	DOC "libiberty include directory containing libiberty.h")
+
+if(LibIberty_INCLUDE_DIRS AND LibIberty_LIBRARIES)
+	set(LibIberty_FOUND TRUE)
+endif()
+
+if(LibIberty_FOUND)
+	if(NOT LibIberty_FIND_QUIETLY)
+		MESSAGE(STATUS "Found libiberty: ${LibIberty_LIBRARIES}")
+	endif()
+else()
+	if(LibIberty_FIND_REQUIRED)
+		MESSAGE(FATAL_ERROR "Could not find libiberty: install binutils-dev or libiberty-dev")
+	else()
+		MESSAGE(STATUS "libiberty not found")
+	endif()
+endif()

doc/how-to-build.txt

@@ -13,7 +13,7 @@ Required for Fail*:
  - protobuf-compiler
  - cmake 2.8.2 (2.8.11 preferred)
  - cmake-curses-gui
- - binutils-dev
+ - binutils-dev, on newer systems libiberty-dev
  - AspectC++ (ag++, ac++): AspectC++ 1.1 or newer is known to work and can be
    obtained from <http://www.aspectc.org>; nightlies can be downloaded from
    <http://akut.aspectc.org>.  Make sure you use the 64-bit version if running

src/core/util/CMakeLists.txt

@@ -43,12 +43,8 @@ include_directories(${Boost_INCLUDE_DIRS})
 link_directories(${Boost_LIBRARY_DIRS})
 
 # libiberty required by Demangler.cc:
-find_library(LIB_IBERTY iberty)
+find_package(LibIberty REQUIRED)
-mark_as_advanced(LIB_IBERTY)
+include_directories(${LibIberty_INCLUDE_DIRS})
-
-if(${LIB_IBERTY} STREQUAL LIB_IBERTY-NOTFOUND)
-  message(FATAL_ERROR "libiberty not found. Try installing binutils-dev: [ sudo aptitude install binutils-dev ]")
-endif()
 
 # libz required by gzstream
 find_package(ZLIB REQUIRED)
@@ -74,7 +70,7 @@ mark_as_advanced(FAIL_OBJDUMP)
 add_library(fail-util ${SRCS})
 add_dependencies(fail-util fail-comm)
 target_link_libraries(fail-util fail-comm)
-target_link_libraries(fail-util ${PROTOBUF_LIBRARY} ${Boost_LIBRARIES} ${LIB_IBERTY} ${ZLIB_LIBRARIES} ${LIBDWARF_LIBRARIES} ${LIBELF_LIBRARIES})
+target_link_libraries(fail-util ${PROTOBUF_LIBRARY} ${Boost_LIBRARIES} ${LibIberty_LIBRARIES} ${ZLIB_LIBRARIES} ${LIBDWARF_LIBRARIES} ${LIBELF_LIBRARIES})
 
 option(BUILD_LLVM_DISASSEMBLER "Build the LLVM-based disassembler (LLVM 3.3 preferred, for 3.1 and 3.2 read doc/how-to-build.txt)" OFF)
 if (BUILD_LLVM_DISASSEMBLER)