diff --git a/boards/arm/imxrt/imxrt1050-evk/configs/libcxxtest/Make.defs b/boards/arm/imxrt/imxrt1050-evk/configs/libcxxtest/Make.defs
index b2c6073c31c..c9fdb8a7a09 100644
--- a/boards/arm/imxrt/imxrt1050-evk/configs/libcxxtest/Make.defs
+++ b/boards/arm/imxrt/imxrt1050-evk/configs/libcxxtest/Make.defs
@@ -3,6 +3,7 @@
 #
 #   Copyright (C) 2018 Gregory Nutt. All rights reserved.
 #   Author: Gregory Nutt <gnutt@nuttx.org>
+#           Daniel Pereira Volpato <dpo@certi.org.br>
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
@@ -101,8 +102,7 @@ CFLAGS = $(ARCHCFLAGS) $(ARCHWARNINGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARC
 CPICFLAGS = $(ARCHPICFLAGS) $(CFLAGS)
 CXXFLAGS  = $(ARCHCXXFLAGS) $(ARCHWARNINGSXX) $(ARCHOPTIMIZATION) \
             $(ARCHCPUFLAGS) $(ARCHXXINCLUDES)
-CXXFLAGS += $(ARCHDEFINES) $(EXTRADEFINES) -pipe -std=c++11 -DCLOCK_MONOTONIC \
-            -D__NuttX__
+CXXFLAGS += $(ARCHDEFINES) $(EXTRADEFINES) -pipe -std=c++11 -D__NuttX__
 CXXFLAGS += -fno-builtin -fno-exceptions -fcheck-new -fno-rtti
 CXXFLAGS += -pedantic -D_DEBUG -D_LIBCPP_BUILD_STATIC -D_LIBCPP_NO_EXCEPTIONS
 CXXPICFLAGS = $(ARCHPICFLAGS) $(CXXFLAGS)
diff --git a/boards/arm/imxrt/imxrt1060-evk/configs/libcxxtest/Make.defs b/boards/arm/imxrt/imxrt1060-evk/configs/libcxxtest/Make.defs
index 4ac29a15726..0702867b206 100644
--- a/boards/arm/imxrt/imxrt1060-evk/configs/libcxxtest/Make.defs
+++ b/boards/arm/imxrt/imxrt1060-evk/configs/libcxxtest/Make.defs
@@ -3,6 +3,7 @@
 #
 #   Copyright (C) 2018 Gregory Nutt. All rights reserved.
 #   Author: Gregory Nutt <gnutt@nuttx.org>
+#           Daniel Pereira Volpato <dpo@certi.org.br>
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
@@ -101,8 +102,7 @@ CFLAGS = $(ARCHCFLAGS) $(ARCHWARNINGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARC
 CPICFLAGS = $(ARCHPICFLAGS) $(CFLAGS)
 CXXFLAGS  = $(ARCHCXXFLAGS) $(ARCHWARNINGSXX) $(ARCHOPTIMIZATION) \
             $(ARCHCPUFLAGS) $(ARCHXXINCLUDES)
-CXXFLAGS += $(ARCHDEFINES) $(EXTRADEFINES) -pipe -std=c++11 -DCLOCK_MONOTONIC \
-            -D__NuttX__
+CXXFLAGS += $(ARCHDEFINES) $(EXTRADEFINES) -pipe -std=c++11 -D__NuttX__
 CXXFLAGS += -fno-builtin -fno-exceptions -fcheck-new -fno-rtti
 CXXFLAGS += -pedantic -D_DEBUG -D_LIBCPP_BUILD_STATIC -D_LIBCPP_NO_EXCEPTIONS
 CXXPICFLAGS = $(ARCHPICFLAGS) $(CXXFLAGS)
diff --git a/boards/arm/lpc43xx/bambino-200e/configs/netnsh/Make.defs b/boards/arm/lpc43xx/bambino-200e/configs/netnsh/Make.defs
index 94cbf030eb3..4161a671932 100644
--- a/boards/arm/lpc43xx/bambino-200e/configs/netnsh/Make.defs
+++ b/boards/arm/lpc43xx/bambino-200e/configs/netnsh/Make.defs
@@ -4,6 +4,7 @@
 #   Copyright (C) 2017 Gregory Nutt. All rights reserved.
 #   Author: Gregory Nutt <gnutt@nuttx.org>
 #           Alan Carvalho de Assis acassis@gmail.com [nuttx] <nuttx@googlegroups.com>
+#           Daniel Pereira Volpato <dpo@certi.org.br>
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
@@ -112,7 +113,7 @@ ARCHPICFLAGS = -fpic -msingle-pic-base -mpic-register=r10
 CFLAGS = $(ARCHCFLAGS) $(ARCHWARNINGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARCHINCLUDES) $(ARCHDEFINES) $(EXTRADEFINES) -pipe
 CPICFLAGS = $(ARCHPICFLAGS) $(CFLAGS)
 CXXFLAGS  = $(ARCHCXXFLAGS) $(ARCHWARNINGSXX) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARCHXXINCLUDES)
-CXXFLAGS += $(ARCHDEFINES) $(EXTRADEFINES) -pipe -std=c++11 -DCLOCK_MONOTONIC -D__NuttX__
+CXXFLAGS += $(ARCHDEFINES) $(EXTRADEFINES) -pipe -std=c++11 -D__NuttX__
 CXXFLAGS += -fno-builtin -fno-exceptions -fcheck-new -fno-rtti
 CXXFLAGS += -pedantic -D_DEBUG -D_LIBCPP_BUILD_STATIC -D_LIBCPP_NO_EXCEPTIONS
 CXXPICFLAGS = $(ARCHPICFLAGS) $(CXXFLAGS)
diff --git a/boards/arm/stm32/stm32f4discovery/configs/testlibcxx/Make.defs b/boards/arm/stm32/stm32f4discovery/configs/testlibcxx/Make.defs
index bab9a4d03d4..fa5904d49f2 100644
--- a/boards/arm/stm32/stm32f4discovery/configs/testlibcxx/Make.defs
+++ b/boards/arm/stm32/stm32f4discovery/configs/testlibcxx/Make.defs
@@ -3,6 +3,7 @@
 #
 #   Copyright (C) 2017 Gregory Nutt. All rights reserved.
 #   Author: Gregory Nutt <gnutt@nuttx.org>
+#           Daniel Pereira Volpato <dpo@certi.org.br>
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
@@ -101,8 +102,7 @@ CFLAGS = $(ARCHCFLAGS) $(ARCHWARNINGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) \
 CPICFLAGS = $(ARCHPICFLAGS) $(CFLAGS)
 CXXFLAGS  = $(ARCHCXXFLAGS) $(ARCHWARNINGSXX) $(ARCHOPTIMIZATION) \
             $(ARCHCPUFLAGS) $(ARCHXXINCLUDES)
-CXXFLAGS += $(ARCHDEFINES) $(EXTRADEFINES) -pipe -std=c++11 -DCLOCK_MONOTONIC \
-            -D__NuttX__
+CXXFLAGS += $(ARCHDEFINES) $(EXTRADEFINES) -pipe -std=c++11 -D__NuttX__
 CXXFLAGS += -fno-builtin -fno-exceptions -fcheck-new -fno-rtti
 CXXFLAGS += -pedantic -D_DEBUG -D_LIBCPP_BUILD_STATIC -D_LIBCPP_NO_EXCEPTIONS
 CXXPICFLAGS = $(ARCHPICFLAGS) $(CXXFLAGS)
diff --git a/libs/libxx/Kconfig b/libs/libxx/Kconfig
index 565098bb261..7aa9eec6102 100644
--- a/libs/libxx/Kconfig
+++ b/libs/libxx/Kconfig
@@ -41,6 +41,7 @@ comment "LLVM C++ Library (libcxx)"
 config LIBCXX
 	bool "Build LLVM libcxx (must be installed)"
 	default n
+	select CLOCK_MONOTONIC
 	select LIBC_WCHAR
 	select TIME_EXTENDED
 	---help---