diff --git a/boards/arm/eoss3/quickfeather/scripts/Make.defs b/boards/arm/eoss3/quickfeather/scripts/Make.defs
index 3e06f19a35..af22bc6dc6 100644
--- a/boards/arm/eoss3/quickfeather/scripts/Make.defs
+++ b/boards/arm/eoss3/quickfeather/scripts/Make.defs
@@ -52,7 +52,7 @@ ARCHPICFLAGS = -fpic -msingle-pic-base -mpic-register=r10
 
 ifeq ($(CONFIG_ARMV7M_TOOLCHAIN_CLANGL),y)
   ARCHCFLAGS += -nostdlib -ffreestanding
-  ARCHCXXFLAGS += -nostdlib -ffreestanding -DCONFIG_WCHAR_BUILTIN
+  ARCHCXXFLAGS += -nostdlib -ffreestanding
 else
   ARCHCFLAGS += -funwind-tables
   ARCHCXXFLAGS += -fno-rtti -funwind-tables
diff --git a/boards/arm/stm32/nucleo-f446re/scripts/Make.defs b/boards/arm/stm32/nucleo-f446re/scripts/Make.defs
index 2feef3693d..de07d18afe 100644
--- a/boards/arm/stm32/nucleo-f446re/scripts/Make.defs
+++ b/boards/arm/stm32/nucleo-f446re/scripts/Make.defs
@@ -59,7 +59,7 @@ ARCHCXXFLAGS = -fno-builtin -fno-exceptions -fcheck-new
 
 ifeq ($(CONFIG_ARMV7M_TOOLCHAIN_CLANGL),y)
   ARCHCFLAGS += -nostdlib -ffreestanding
-  ARCHCXXFLAGS += -nostdlib -ffreestanding -DCONFIG_WCHAR_BUILTIN
+  ARCHCXXFLAGS += -nostdlib -ffreestanding
 else
   ARCHCXXFLAGS += -fno-rtti
   ifneq ($(CONFIG_DEBUG_NOOPT),y)
diff --git a/boards/arm/stm32/nucleo-f4x1re/scripts/Make.defs b/boards/arm/stm32/nucleo-f4x1re/scripts/Make.defs
index 523a2788ab..4306e01bea 100644
--- a/boards/arm/stm32/nucleo-f4x1re/scripts/Make.defs
+++ b/boards/arm/stm32/nucleo-f4x1re/scripts/Make.defs
@@ -65,7 +65,7 @@ ARCHCXXFLAGS = -fno-builtin -fno-exceptions -fcheck-new
 
 ifeq ($(CONFIG_ARMV7M_TOOLCHAIN_CLANGL),y)
   ARCHCFLAGS += -nostdlib -ffreestanding
-  ARCHCXXFLAGS += -nostdlib -ffreestanding DCONFIG_WCHAR_BUILTIN
+  ARCHCXXFLAGS += -nostdlib -ffreestanding
 else
   ARCHCXXFLAGS += -fno-rtti
   ifneq ($(CONFIG_DEBUG_NOOPT),y)
diff --git a/boards/arm/stm32/stm32f4discovery/scripts/Make.defs b/boards/arm/stm32/stm32f4discovery/scripts/Make.defs
index 59aa60bf6b..cddea9f0aa 100644
--- a/boards/arm/stm32/stm32f4discovery/scripts/Make.defs
+++ b/boards/arm/stm32/stm32f4discovery/scripts/Make.defs
@@ -46,7 +46,7 @@ ARCHPICFLAGS = -fpic -msingle-pic-base -mpic-register=r10
 
 ifeq ($(CONFIG_ARMV7M_TOOLCHAIN_CLANGL),y)
   ARCHCFLAGS += -nostdlib -ffreestanding
-  ARCHCXXFLAGS += -nostdlib -ffreestanding -DCONFIG_WCHAR_BUILTIN
+  ARCHCXXFLAGS += -nostdlib -ffreestanding
 else
   ARCHCFLAGS += -funwind-tables
   ARCHCXXFLAGS += -fno-rtti -funwind-tables
diff --git a/boards/arm/stm32f7/stm32f746g-disco/scripts/Make.defs b/boards/arm/stm32f7/stm32f746g-disco/scripts/Make.defs
index 2639e5bf16..09ae0640c9 100644
--- a/boards/arm/stm32f7/stm32f746g-disco/scripts/Make.defs
+++ b/boards/arm/stm32f7/stm32f746g-disco/scripts/Make.defs
@@ -54,7 +54,7 @@ ARCHCXXFLAGS = -fno-builtin -fno-exceptions -fcheck-new -fno-rtti
 
 ifeq ($(CONFIG_ARMV7M_TOOLCHAIN_CLANGL),y)
   ARCHCFLAGS += -nostdlib -ffreestanding
-  ARCHCXXFLAGS += -nostdlib -ffreestanding -DCONFIG_WCHAR_BUILTIN
+  ARCHCXXFLAGS += -nostdlib -ffreestanding
 else
   ARCHCXXFLAGS += -fno-rtti
   ifneq ($(CONFIG_DEBUG_NOOPT),y)
diff --git a/tools/ide_exporter.py b/tools/ide_exporter.py
index 9d5f9e363f..543164acda 100755
--- a/tools/ide_exporter.py
+++ b/tools/ide_exporter.py
@@ -957,7 +957,6 @@ if __name__ == '__main__':
             lib_prj.make_output_dir(lib_name)
             if lib_name == 'libxx':
                 lib_prj.add_misc('cxx_misc')
-                lib_prj.add_define('cxx_def', 'CONFIG_WCHAR_BUILTIN')
             else:
                 lib_prj.add_misc('c_misc')