diff --git a/config/config.mk b/config/config.mk
index 791abf82822f..5367f357865e 100644
--- a/config/config.mk
+++ b/config/config.mk
@@ -133,6 +133,7 @@ endif
 # Enable profile-based feedback
 ifneq (1,$(NO_PROFILE_GUIDED_OPTIMIZE))
 ifdef MOZ_PROFILE_GENERATE
+PGO_CFLAGS += -DNS_FREE_PERMANENT_DATA=1
 PGO_CFLAGS += $(if $(filter $(notdir $<),$(notdir $(NO_PROFILE_GUIDED_OPTIMIZE))),,$(PROFILE_GEN_CFLAGS))
 PGO_LDFLAGS += $(PROFILE_GEN_LDFLAGS)
 ifeq (WINNT,$(OS_ARCH))
diff --git a/xpcom/base/nscore.h b/xpcom/base/nscore.h
index 984e719c8193..07e76ba4ddd8 100644
--- a/xpcom/base/nscore.h
+++ b/xpcom/base/nscore.h
@@ -172,11 +172,13 @@
  * if we're using _exit. Bug 1555974 covers improving this.
  *
  */
+#ifndef NS_FREE_PERMANENT_DATA
 #if defined(NS_BUILD_REFCNT_LOGGING) || defined(MOZ_VALGRIND) || \
     defined(MOZ_ASAN) || defined(MOZ_CODE_COVERAGE) ||           \
     defined(MOZ_PROFILE_GENERATE)
 #  define NS_FREE_PERMANENT_DATA
 #endif
+#endif
 
 /**
  * NS_NO_VTABLE is emitted by xpidl in interface declarations whenever