Remove automatic use of gperftools on non-Linux systems.

--enable-perftools must now explicity be supplied to ./configure on
non-Linux systems to link against the tcmalloc library that a
gperftools installation provides.  Linux systems still automatically
link it if it's found.  The rationale is that gperftools was developed
and most throroughly tested on Linux so it's safer there.

There especially seems to be potential problems with gperftools on OS X
(e.g. see http://code.google.com/p/gperftools/issues/detail?id=413),
and Bro currently doesn't work with gpertools there using clang or gcc.

CMakeLists.txt

@@ -88,25 +88,31 @@ if (LIBGEOIP_FOUND)
     list(APPEND OPTLIBS ${LibGeoIP_LIBRARY})
 endif ()
 
-set(USE_PERFTOOLS false)
+set(HAVE_PERFTOOLS false)
 set(USE_PERFTOOLS_DEBUG false)
+set(USE_PERFTOOLS_TCMALLOC false)
 
 if (NOT DISABLE_PERFTOOLS)
    find_package(GooglePerftools)
 endif ()
 
 if (GOOGLEPERFTOOLS_FOUND)
-    include_directories(BEFORE ${GooglePerftools_INCLUDE_DIR})
+    set(HAVE_PERFTOOLS true)
-    set(USE_PERFTOOLS true)
+    # Non-Linux systems may not be well-supported by gperftools, so
+    # require explicit request from user to enable it in that case.
+    if (${CMAKE_SYSTEM_NAME} MATCHES "Linux" OR ENABLE_PERFTOOLS)
+        set(USE_PERFTOOLS_TCMALLOC true)
 
         if (ENABLE_PERFTOOLS_DEBUG)
             # Enable heap debugging with perftools.
             set(USE_PERFTOOLS_DEBUG true)
+            include_directories(BEFORE ${GooglePerftools_INCLUDE_DIR})
             list(APPEND OPTLIBS ${GooglePerftools_LIBRARIES_DEBUG})
         else ()
             # Link in tcmalloc for better performance.
             list(APPEND OPTLIBS ${GooglePerftools_LIBRARIES})
         endif ()
+    endif ()
 endif ()
 
 set(USE_DATASERIES false)
@@ -224,7 +230,8 @@ message(
     "\nAux. Tools:        ${INSTALL_AUX_TOOLS}"
     "\n"
     "\nGeoIP:             ${USE_GEOIP}"
-    "\nGoogle perftools:  ${USE_PERFTOOLS}"
+    "\ngperftools found:  ${HAVE_PERFTOOLS}"
+    "\n        tcmalloc:  ${USE_PERFTOOLS_TCMALLOC}"
     "\n       debugging:  ${USE_PERFTOOLS_DEBUG}"
     "\ncURL:              ${USE_CURL}"
     "\n"

configure

@@ -29,6 +29,8 @@ Usage: $0 [OPTION]... [VAR=VALUE]...
   Optional Features:
     --enable-debug         compile in debugging mode
     --enable-mobile-ipv6   analyze mobile IPv6 features defined by RFC 6275
+    --enable-perftools     force use of Google perftools on non-Linux systems
+                           (automatically on when perftools is present on Linux)
     --enable-perftools-debug use Google's perftools for debugging
     --disable-broccoli     don't build or install the Broccoli library
     --disable-broctl       don't install Broctl
@@ -98,6 +100,7 @@ append_cache_entry PY_MOD_INSTALL_DIR   PATH   $prefix/lib/broctl
 append_cache_entry BRO_SCRIPT_INSTALL_PATH STRING $prefix/share/bro
 append_cache_entry BRO_ETC_INSTALL_DIR  PATH   $prefix/etc
 append_cache_entry ENABLE_DEBUG         BOOL   false
+append_cache_entry ENABLE_PERFTOOLS     BOOL   false
 append_cache_entry ENABLE_PERFTOOLS_DEBUG BOOL false
 append_cache_entry BinPAC_SKIP_INSTALL  BOOL   true
 append_cache_entry BUILD_SHARED_LIBS    BOOL   true
@@ -146,7 +149,11 @@ while [ $# -ne 0 ]; do
         --enable-mobile-ipv6)
             append_cache_entry ENABLE_MOBILE_IPV6         BOOL   true
             ;;
+        --enable-perftools)
+            append_cache_entry ENABLE_PERFTOOLS     BOOL   true
+            ;;
         --enable-perftools-debug)
+            append_cache_entry ENABLE_PERFTOOLS     BOOL   true
             append_cache_entry ENABLE_PERFTOOLS_DEBUG BOOL   true
             ;;
         --disable-broccoli)