diff --git a/external/gpl2/lvm2/dist/include/lib.h b/external/gpl2/lvm2/dist/include/lib.h
index 6c8d5366da9d..e704a5b01736 100644
--- a/external/gpl2/lvm2/dist/include/lib.h
+++ b/external/gpl2/lvm2/dist/include/lib.h
@@ -23,7 +23,9 @@
 
 #include "configure.h"
 
+#ifndef _REENTRANT
 #define _REENTRANT
+#endif
 #define _GNU_SOURCE
 #define _FILE_OFFSET_BITS 64
 
diff --git a/external/gpl2/lvm2/lvm2tools.mk b/external/gpl2/lvm2/lvm2tools.mk
index ff04b2a8b0b4..54a1ba59d2e1 100644
--- a/external/gpl2/lvm2/lvm2tools.mk
+++ b/external/gpl2/lvm2/lvm2tools.mk
@@ -24,7 +24,3 @@ CPPFLAGS+=-DDM_DEVICE_UID=0 -DDM_DEVICE_GID=5 -DDM_DEVICE_MODE=0640 \
 #.endif
 #
 #LVM2.liblvm=	${LVM2OBJDIR.liblvm}/liblvm.a
-
-.if ${MKSANITIZER:Uno} == "yes" || ${MKLIBCSANITIZER:Uno} == "yes"
-CFLAGS+=	-Wno-macro-redefined # _REENTRANT redefined in lib.h
-.endif