cmake: libebl was merged into libdw

Since elfutils 178, libebl is now part of libdw, so searching for libebl
always fails. Simply remove it from the search.

Reviewer notes:

I even built dwarves with the patch against and old elfutils-0.176 and a
new elfutils-0.178 to double check. Builds fine with both.

With elfutils-0.178 pahole even automagically works with the new
debuginfo-client support.  See

https://sourceware.org/elfutils/Debuginfod.html

Signed-off-by: Jason A. Donenfeld <[email protected]>
Reviewed-by: Mark Wielaard <[email protected]>
Cc: [email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

cmake/modules/FindDWARF.cmake

@@ -37,33 +37,27 @@ find_library(ELF_LIBRARY
 	PATHS /usr/lib /usr/local/lib /usr/lib64 /usr/local/lib64 ~/usr/local/lib ~/usr/local/lib64
 )
 
-find_library(EBL_LIBRARY
-	NAMES ebl
-	PATHS /usr/lib /usr/local/lib /usr/lib64 /usr/local/lib64 ~/usr/local/lib ~/usr/local/lib64
-)
-
-if (DWARF_INCLUDE_DIR AND LIBDW_INCLUDE_DIR AND DWARF_LIBRARY AND ELF_LIBRARY AND EBL_LIBRARY)
+if (DWARF_INCLUDE_DIR AND LIBDW_INCLUDE_DIR AND DWARF_LIBRARY AND ELF_LIBRARY)
 	set(DWARF_FOUND TRUE)
-	set(DWARF_LIBRARIES ${DWARF_LIBRARY} ${ELF_LIBRARY} ${EBL_LIBRARY})
+	set(DWARF_LIBRARIES ${DWARF_LIBRARY} ${ELF_LIBRARY})
 
 	set(CMAKE_REQUIRED_LIBRARIES ${DWARF_LIBRARIES})
 	# check if libdw have the dwfl_module_build_id routine, i.e. if it supports the buildid
 	# mechanism to match binaries to detached debug info sections (the -debuginfo packages
 	# in distributions such as fedora). We do it against libelf because, IIRC, some distros
 	# include libdw linked statically into libelf.
 	check_library_exists(elf dwfl_module_build_id "" HAVE_DWFL_MODULE_BUILD_ID)
-else (DWARF_INCLUDE_DIR AND LIBDW_INCLUDE_DIR AND DWARF_LIBRARY AND ELF_LIBRARY AND EBL_LIBRARY)
+else (DWARF_INCLUDE_DIR AND LIBDW_INCLUDE_DIR AND DWARF_LIBRARY AND ELF_LIBRARY)
 	set(DWARF_FOUND FALSE)
 	set(DWARF_LIBRARIES)
-endif (DWARF_INCLUDE_DIR AND LIBDW_INCLUDE_DIR AND DWARF_LIBRARY AND ELF_LIBRARY AND EBL_LIBRARY)
+endif (DWARF_INCLUDE_DIR AND LIBDW_INCLUDE_DIR AND DWARF_LIBRARY AND ELF_LIBRARY)
 
 if (DWARF_FOUND)
 	if (NOT DWARF_FIND_QUIETLY)
 		message(STATUS "Found dwarf.h header: ${DWARF_INCLUDE_DIR}")
 		message(STATUS "Found elfutils/libdw.h header: ${LIBDW_INCLUDE_DIR}")
 		message(STATUS "Found libdw library: ${DWARF_LIBRARY}")
 		message(STATUS "Found libelf library: ${ELF_LIBRARY}")
-		message(STATUS "Found libebl library: ${EBL_LIBRARY}")
 	endif (NOT DWARF_FIND_QUIETLY)
 else (DWARF_FOUND)
 	if (DWARF_FIND_REQUIRED)
@@ -73,9 +67,9 @@ else (DWARF_FOUND)
 		find_path(FEDORA fedora-release /etc)
 		find_path(REDHAT redhat-release /etc)
 		if (FEDORA OR REDHAT)
-			if (NOT DWARF_INCLUDE_DIR OR NOT LIBDW_INCLUDE_DIR OR NOT EBL_LIBRARY)
+			if (NOT DWARF_INCLUDE_DIR OR NOT LIBDW_INCLUDE_DIR)
 				message(STATUS "Please install the elfutils-devel package")
-			endif (NOT DWARF_INCLUDE_DIR OR NOT LIBDW_INCLUDE_DIR OR NOT EBL_LIBRARY)
+			endif (NOT DWARF_INCLUDE_DIR OR NOT LIBDW_INCLUDE_DIR)
 			if (NOT DWARF_LIBRARY)
 				message(STATUS "Please install the elfutils-libs package")
 			endif (NOT DWARF_LIBRARY)
@@ -89,9 +83,6 @@ else (DWARF_FOUND)
 			if (NOT LIBDW_INCLUDE_DIR)
 				message(STATUS "Could NOT find libdw include dir")
 			endif (NOT LIBDW_INCLUDE_DIR)
-			if (NOT EBL_LIBRARY)
-				message(STATUS "Could NOT find libebl library")
-			endif (NOT EBL_LIBRARY)
 			if (NOT DWARF_LIBRARY)
 				message(STATUS "Could NOT find libdw library")
 			endif (NOT DWARF_LIBRARY)
@@ -103,7 +94,7 @@ else (DWARF_FOUND)
 	endif (DWARF_FIND_REQUIRED)
 endif (DWARF_FOUND)
 
-mark_as_advanced(DWARF_INCLUDE_DIR LIBDW_INCLUDE_DIR DWARF_LIBRARY ELF_LIBRARY EBL_LIBRARY)
+mark_as_advanced(DWARF_INCLUDE_DIR LIBDW_INCLUDE_DIR DWARF_LIBRARY ELF_LIBRARY)
 include_directories(${DWARF_INCLUDE_DIR} ${LIBDW_INCLUDE_DIR})
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/config.h.cmake ${CMAKE_CURRENT_SOURCE_DIR}/config.h)