Enable link-time optimization on *nix platforms

rebar.config

@@ -8,12 +8,12 @@
 
 {port_env, [
     {"(linux|solaris|freebsd|netbsd|openbsd|dragonfly|darwin|gnu)",
-        "CFLAGS", "$CFLAGS -Ic_src/ -g -Wall -Werror -O3 -fno-strict-aliasing"},
+        "CFLAGS", "$CFLAGS -Ic_src/ -g -Wall -flto -Werror -O3 -fno-strict-aliasing"},
     {"(linux|solaris|freebsd|netbsd|openbsd|dragonfly|darwin|gnu)",
-        "CXXFLAGS", "$CXXFLAGS -Ic_src/ -g -Wall -Werror -O3"},
+        "CXXFLAGS", "$CXXFLAGS -Ic_src/ -g -Wall -flto -Werror -O3"},
 
     {"(linux|solaris|freebsd|netbsd|openbsd|dragonfly|darwin|gnu)",
-        "LDFLAGS", "$LDFLAGS -lstdc++"},
+        "LDFLAGS", "$LDFLAGS -flto -lstdc++"},
 
     %% OS X Leopard flags for 64-bit
     {"darwin9.*-64$", "CXXFLAGS", "-m64"},