Add -Djemalloc option

now it is possible to use both tcmalloc and jemalloc allocators within
ROOT w/o the need of preloading. This can be an asset also in the context
of a multithreaded environment.

CMakeLists.txt

@@ -52,6 +52,12 @@ if (TCMALLOC_FOUND)
   set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -ltcmalloc")
 endif()
 
+#---Here we add jemalloc to the linker flags if needed------------------------------------------
+if (JEMALLOC_FOUND)
+  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -ljemalloc")
+  set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -ljemalloc")
+endif()
+
 #---Populate the configure arguments returned by 'root-config --config'-------------------------
 get_cmake_property(variables CACHE_VARIABLES)
 foreach(var ${variables})

cmake/modules/RootBuildOptions.cmake

@@ -131,6 +131,7 @@ ROOT_BUILD_OPTION(globus OFF "Globus authentication support, requires Globus too
 ROOT_BUILD_OPTION(gsl_shared OFF "Enable linking against shared libraries for GSL (default no)")
 ROOT_BUILD_OPTION(hdfs ON "HDFS support; requires libhdfs from HDFS >= 0.19.1")
 ROOT_BUILD_OPTION(http ${http_defvalue} "HTTP Server support")
+ROOT_BUILD_OPTION(jemalloc OFF "Using the jemalloc allocator")
 ROOT_BUILD_OPTION(krb5 ON "Kerberos5 support, requires Kerberos libs")
 ROOT_BUILD_OPTION(ldap ON "LDAP support, requires (Open)LDAP libs")
 ROOT_BUILD_OPTION(mathmore ON "Build the new libMathMore extended math library, requires GSL (vers. >= 1.8)")

cmake/modules/SearchInstalledSoftware.cmake

@@ -853,6 +853,19 @@ if (tcmalloc)
   endif()
 endif()
 
+#---Check for JEMalloc---------------------------------------------------------------
+
+if (jemalloc)
+  if (tcmalloc)
+   message(FATAL_ERROR "Both tcmalloc and jemalloc were selected: this is an inconsistent setup.")
+  endif()
+  message(STATUS "Looking for jemalloc")
+  find_package(jemalloc)
+  if(NOT JEMALLOC_FOUND)
+    message(STATUS "JEMalloc not found.")
+  endif()
+endif()
+
 #---Report non implemented options---------------------------------------------------
 foreach(opt afs clarens glite pch peac sapdb srp geocad)
   if(${opt})