diff --git a/builds/posix/prefix.darwin_i386 b/builds/posix/prefix.darwin_i386
index 789549c88e..9634d07e41 100644
--- a/builds/posix/prefix.darwin_i386
+++ b/builds/posix/prefix.darwin_i386
@@ -27,6 +27,7 @@ OS_ServerFiles=inet_server.cpp
 
 PROD_FLAGS=-O3 -DNDEBUG -DDARWIN -pipe -p -MMD -fPIC -fno-common -arch i386 -mmacosx-version-min=10.4
 DEV_FLAGS=-ggdb -DDARWIN -pipe -p -MMD -fPIC -fno-common -Wall -arch i386 -mmacosx-version-min=10.4
+CXXFLAGS:=$(CXXFLAGS) -fvisibility-inlines-hidden -fvisibility=hidden
 EMBED_UTIL_TARGETS=gstat gds_drop gds_relay gsec fbguard nbackup fb_lock_print fbsvcmgr
 CLIENT_UTIL_TARGETS=gds_drop gds_relay gstat gsec fbguard fbmgr_bin nbackup fb_lock_print fbsvcmgr