diff --git a/ChangeLog b/ChangeLog
index 2dc2160..d249e1c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 2017-11-20  NIIBE Yutaka  <gniibe@fsij.org>
 
+	* example-led: Update using stack-def.h.
+
 	* chopstx-cortex-m.c [__ARM_ARCH_6M__] (chx_sched): Fix.
 
 2017-11-18  NIIBE Yutaka  <gniibe@fsij.org>
diff --git a/example-led/sample.c b/example-led/sample.c
index f346676..7e7bcff 100644
--- a/example-led/sample.c
+++ b/example-led/sample.c
@@ -72,14 +72,17 @@ blk (void *arg)
 #define PRIO_BLK 2
 #endif
 
-extern uint8_t __process1_stack_base__[], __process1_stack_size__[];
-extern uint8_t __process2_stack_base__[], __process2_stack_size__[];
+#define STACK_MAIN
+#define STACK_PROCESS_1
+#define STACK_PROCESS_2
+#include "stack-def.h"
 
-#define STACK_ADDR_PWM ((uint32_t)__process1_stack_base__)
-#define STACK_SIZE_PWM ((uint32_t)__process1_stack_size__)
 
-#define STACK_ADDR_BLK ((uint32_t)__process2_stack_base__)
-#define STACK_SIZE_BLK ((uint32_t)__process2_stack_size__)
+#define STACK_ADDR_PWM ((uint32_t)process1_base)
+#define STACK_SIZE_PWM (sizeof process1_base)
+
+#define STACK_ADDR_BLK ((uint32_t)process2_base)
+#define STACK_SIZE_BLK (sizeof process2_base)
 
 
 int
diff --git a/example-led/sample.ld b/example-led/sample.ld
index 42a765d..a9be67f 100644
--- a/example-led/sample.ld
+++ b/example-led/sample.ld
@@ -1,12 +1,6 @@
 /*
  * ST32F0 memory setup.
  */
-__main_stack_size__      = 0x0100; /* Idle+Exception handlers */
-__process0_stack_size__  = 0x0100; /* Main program            */
-__process1_stack_size__  = 0x0100; /* first thread program    */
-__process2_stack_size__  = 0x0100; /* second thread program   */
-__process3_stack_size__  = 0x0100; /* third thread program    */
-
 MEMORY
 {
     flash0 : org = 0x08000000, len = 4k
@@ -87,34 +81,15 @@ SECTIONS
 	KEEP(*(.bss.startup.*))
     } > ram
 
-    .process_stack :
+    .stacks (NOLOAD) :
     {
         . = ALIGN(8);
-        __process3_stack_base__ = .;
-        . += __process3_stack_size__;
+        *(.main_stack)
+        *(.process_stack.0)
+        *(.process_stack.1)
+        *(.process_stack.2)
+        *(.process_stack.3)
         . = ALIGN(8);
-        __process3_stack_end__ = .;
-        __process2_stack_base__ = .;
-        . += __process2_stack_size__;
-        . = ALIGN(8);
-        __process2_stack_end__ = .;
-        __process1_stack_base__ = .;
-        . += __process1_stack_size__;
-        . = ALIGN(8);
-        __process1_stack_end__ = .;
-        __process0_stack_base__ = .;
-        . += __process0_stack_size__;
-        . = ALIGN(8);
-        __process0_stack_end__ = .;
-    } > ram
-
-    .main_stack :
-    {
-        . = ALIGN(8);
-        __main_stack_base__ = .;
-        . += __main_stack_size__;
-        . = ALIGN(8);
-        __main_stack_end__ = .;
     } > ram
 
     .data :
diff --git a/example-led/sample.ld.m3 b/example-led/sample.ld.m3
index 842ba86..57ddb83 100644
--- a/example-led/sample.ld.m3
+++ b/example-led/sample.ld.m3
@@ -1,12 +1,6 @@
 /*
  * ST32F103 memory setup.
  */
-__main_stack_size__      = 0x0100; /* Idle+Exception handlers */
-__process0_stack_size__  = 0x0100; /* Main program            */
-__process1_stack_size__  = 0x0100; /* first thread program    */
-__process2_stack_size__  = 0x0100; /* second thread program   */
-__process3_stack_size__  = 0x0100; /* third thread program    */
-
 MEMORY
 {
     flash0 : org = 0x08000000, len = 4k
@@ -78,34 +72,14 @@ SECTIONS
     _etext = .;
     _textdata = _etext;
 
-    .process_stack :
+    .stacks (NOLOAD) :
     {
+        *(.main_stack)
+        *(.process_stack.0)
+        *(.process_stack.1)
+        *(.process_stack.2)
+        *(.process_stack.3)
         . = ALIGN(8);
-        __process3_stack_base__ = .;
-        . += __process3_stack_size__;
-        . = ALIGN(8);
-        __process3_stack_end__ = .;
-        __process2_stack_base__ = .;
-        . += __process2_stack_size__;
-        . = ALIGN(8);
-        __process2_stack_end__ = .;
-        __process1_stack_base__ = .;
-        . += __process1_stack_size__;
-        . = ALIGN(8);
-        __process1_stack_end__ = .;
-        __process0_stack_base__ = .;
-        . += __process0_stack_size__;
-        . = ALIGN(8);
-        __process0_stack_end__ = .;
-    } > ram
-
-    .main_stack :
-    {
-        . = ALIGN(8);
-        __main_stack_base__ = .;
-        . += __main_stack_size__;
-        . = ALIGN(8);
-        __main_stack_end__ = .;
     } > ram
 
     .data :