diff --git a/include/toolchain/gcc.h b/include/toolchain/gcc.h
index e8be67633ef..ea6a0dd9227 100644
--- a/include/toolchain/gcc.h
+++ b/include/toolchain/gcc.h
@@ -194,6 +194,10 @@ do {                                                                    \
 
 #define popcount(x) __builtin_popcount(x)
 
+#ifndef __no_optimization
+#define __no_optimization __attribute__((optimize("-O0")))
+#endif
+
 #ifndef __weak
 #define __weak __attribute__((__weak__))
 #endif
diff --git a/include/toolchain/mwdt.h b/include/toolchain/mwdt.h
index 3eb83fb3bd0..a97f8a05618 100644
--- a/include/toolchain/mwdt.h
+++ b/include/toolchain/mwdt.h
@@ -61,6 +61,8 @@
 
 #else /* defined(_ASMLANGUAGE) */
 
+#define __no_optimization __attribute__((optnone))
+
 #include <toolchain/gcc.h>
 
 /* Metaware toolchain has _Static_assert. However it not able to calculate
diff --git a/tests/kernel/gen_isr_table/src/main.c b/tests/kernel/gen_isr_table/src/main.c
index 1a7cb53b7d8..cdb9f80ce5d 100644
--- a/tests/kernel/gen_isr_table/src/main.c
+++ b/tests/kernel/gen_isr_table/src/main.c
@@ -160,7 +160,7 @@ void isr6(const void *param)
  * doesn't support this; we need to tell the compiler not to reorder memory
  * accesses to trigger_check around calls to trigger_irq.
  */
-__attribute__((optimize("-O0")))
+__no_optimization
 #endif
 int test_irq(int offset)
 {