diff --git a/examples/platforms/cc1352/arm-none-eabi.cmake b/examples/platforms/cc1352/arm-none-eabi.cmake
index c2789c3a5..4b4c67d47 100644
--- a/examples/platforms/cc1352/arm-none-eabi.cmake
+++ b/examples/platforms/cc1352/arm-none-eabi.cmake
@@ -36,15 +36,7 @@ set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
 
 set(COMMON_C_FLAGS                 "-mcpu=cortex-m4 -march=armv7e-m -mfloat-abi=hard -mfpu=fpv4-sp-d16 -mthumb -fdata-sections -ffunction-sections")
 
-set(CMAKE_C_FLAGS                  "${COMMON_C_FLAGS} -std=gnu99")
-set(CMAKE_CXX_FLAGS                "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
-set(CMAKE_ASM_FLAGS                "${COMMON_C_FLAGS}")
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=gnu99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_ASM_FLAGS_INIT           "${COMMON_C_FLAGS}")
 set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -nostartfiles -specs=nano.specs -specs=nosys.specs")
-
-set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
-set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
-set(CMAKE_ASM_FLAGS_DEBUG          "-g")
-
-set(CMAKE_C_FLAGS_RELEASE          "-Os")
-set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
-set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/cc2538/arm-none-eabi.cmake b/examples/platforms/cc2538/arm-none-eabi.cmake
index dc06caed5..2e39ec11d 100644
--- a/examples/platforms/cc2538/arm-none-eabi.cmake
+++ b/examples/platforms/cc2538/arm-none-eabi.cmake
@@ -36,15 +36,7 @@ set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
 
 set(COMMON_C_FLAGS                 "-mthumb -fno-builtin -Wall -fdata-sections -ffunction-sections -mabi=aapcs -mcpu=cortex-m3 -mfloat-abi=soft")
 
-set(CMAKE_C_FLAGS                  "${COMMON_C_FLAGS} -std=gnu99")
-set(CMAKE_CXX_FLAGS                "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
-set(CMAKE_ASM_FLAGS                "${COMMON_C_FLAGS}")
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=gnu99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_ASM_FLAGS_INIT           "${COMMON_C_FLAGS}")
 set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs -nostartfiles")
-
-set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
-set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
-set(CMAKE_ASM_FLAGS_DEBUG          "-g")
-
-set(CMAKE_C_FLAGS_RELEASE          "-Os")
-set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
-set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/cc2650/arm-none-eabi.cmake b/examples/platforms/cc2650/arm-none-eabi.cmake
index c889e39f0..6dba6fdb1 100644
--- a/examples/platforms/cc2650/arm-none-eabi.cmake
+++ b/examples/platforms/cc2650/arm-none-eabi.cmake
@@ -36,15 +36,7 @@ set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
 
 set(COMMON_C_FLAGS                 "-mthumb -fdata-sections -ffunction-sections -mcpu=cortex-m3 -mfloat-abi=soft")
 
-set(CMAKE_C_FLAGS                  "${COMMON_C_FLAGS} -std=gnu99")
-set(CMAKE_CXX_FLAGS                "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
-set(CMAKE_ASM_FLAGS                "${COMMON_C_FLAGS}")
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=gnu99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_ASM_FLAGS_INIT           "${COMMON_C_FLAGS}")
 set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs -nostartfiles")
-
-set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
-set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
-set(CMAKE_ASM_FLAGS_DEBUG          "-g")
-
-set(CMAKE_C_FLAGS_RELEASE          "-Os")
-set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
-set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/cc2652/arm-none-eabi.cmake b/examples/platforms/cc2652/arm-none-eabi.cmake
index bd81b366a..231518175 100644
--- a/examples/platforms/cc2652/arm-none-eabi.cmake
+++ b/examples/platforms/cc2652/arm-none-eabi.cmake
@@ -36,15 +36,7 @@ set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
 
 set(COMMON_C_FLAGS                 "-mcpu=cortex-m4 -march=armv7e-m -mfloat-abi=hard -mfpu=fpv4-sp-d16 -mthumb -fdata-sections -ffunction-sections")
 
-set(CMAKE_C_FLAGS                  "${COMMON_C_FLAGS} -std=gnu99")
-set(CMAKE_CXX_FLAGS                "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
-set(CMAKE_ASM_FLAGS                "${COMMON_C_FLAGS}")
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=gnu99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_ASM_FLAGS_INIT           "${COMMON_C_FLAGS}")
 set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -nostartfiles -specs=nano.specs -specs=nosys.specs -Wl,-Map=map.map")
-
-set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
-set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
-set(CMAKE_ASM_FLAGS_DEBUG          "-g")
-
-set(CMAKE_C_FLAGS_RELEASE          "-Os")
-set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
-set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/kw41z/arm-none-eabi.cmake b/examples/platforms/kw41z/arm-none-eabi.cmake
index d67bcb61a..7484ec9df 100644
--- a/examples/platforms/kw41z/arm-none-eabi.cmake
+++ b/examples/platforms/kw41z/arm-none-eabi.cmake
@@ -36,15 +36,7 @@ set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
 
 set(COMMON_C_FLAGS                 "-mthumb -fdata-sections -ffunction-sections -mcpu=cortex-m0plus -mfloat-abi=soft")
 
-set(CMAKE_C_FLAGS                  "${COMMON_C_FLAGS} -std=gnu99")
-set(CMAKE_CXX_FLAGS                "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
-set(CMAKE_ASM_FLAGS                "${COMMON_C_FLAGS}")
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=gnu99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_ASM_FLAGS_INIT           "${COMMON_C_FLAGS}")
 set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs")
-
-set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
-set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
-set(CMAKE_ASM_FLAGS_DEBUG          "-g")
-
-set(CMAKE_C_FLAGS_RELEASE          "-Os")
-set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
-set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/qpg6095/arm-none-eabi.cmake b/examples/platforms/qpg6095/arm-none-eabi.cmake
index 227520aca..de1ed14aa 100644
--- a/examples/platforms/qpg6095/arm-none-eabi.cmake
+++ b/examples/platforms/qpg6095/arm-none-eabi.cmake
@@ -36,15 +36,7 @@ set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
 
 set(COMMON_C_FLAGS                 "-mcpu=cortex-m4 -mthumb -fdata-sections -ffunction-sections")
 
-set(CMAKE_C_FLAGS                  "${COMMON_C_FLAGS} -std=gnu99")
-set(CMAKE_CXX_FLAGS                "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
-set(CMAKE_ASM_FLAGS                "${COMMON_C_FLAGS}")
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=gnu99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_ASM_FLAGS_INIT           "${COMMON_C_FLAGS}")
 set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs")
-
-set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
-set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
-set(CMAKE_ASM_FLAGS_DEBUG          "-g")
-
-set(CMAKE_C_FLAGS_RELEASE          "-Os")
-set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
-set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/examples/platforms/samr21/arm-none-eabi.cmake b/examples/platforms/samr21/arm-none-eabi.cmake
index ff983a5ed..8ae2e8f34 100644
--- a/examples/platforms/samr21/arm-none-eabi.cmake
+++ b/examples/platforms/samr21/arm-none-eabi.cmake
@@ -36,15 +36,7 @@ set(CMAKE_RANLIB                   arm-none-eabi-ranlib)
 
 set(COMMON_C_FLAGS                 "-mcpu=cortex-m0plus -mfloat-abi=soft -mthumb -fdata-sections -ffunction-sections")
 
-set(CMAKE_C_FLAGS                  "${COMMON_C_FLAGS} -std=gnu99")
-set(CMAKE_CXX_FLAGS                "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
-set(CMAKE_ASM_FLAGS                "${COMMON_C_FLAGS}")
+set(CMAKE_C_FLAGS_INIT             "${COMMON_C_FLAGS} -std=gnu99")
+set(CMAKE_CXX_FLAGS_INIT           "${COMMON_C_FLAGS} -fno-exceptions -fno-rtti")
+set(CMAKE_ASM_FLAGS_INIT           "${COMMON_C_FLAGS}")
 set(CMAKE_EXE_LINKER_FLAGS_INIT    "${COMMON_C_FLAGS} -specs=nano.specs -specs=nosys.specs -Wl,--entry=Reset_Handler")
-
-set(CMAKE_C_FLAGS_DEBUG            "-Og -g")
-set(CMAKE_CXX_FLAGS_DEBUG          "-Og -g")
-set(CMAKE_ASM_FLAGS_DEBUG          "-g")
-
-set(CMAKE_C_FLAGS_RELEASE          "-Os")
-set(CMAKE_CXX_FLAGS_RELEASE        "-Os")
-set(CMAKE_ASM_FLAGS_RELEASE        "")
diff --git a/script/cmake-build b/script/cmake-build
index a5c7f0ad5..02c56daf1 100755
--- a/script/cmake-build
+++ b/script/cmake-build
@@ -152,10 +152,10 @@ main()
             ;;
         cc2650)
             OT_CMAKE_NINJA_TARGET=("ot-cli-mtd" "ot-ncp-mtd")
-            options+=("-DCMAKE_TOOLCHAIN_FILE=examples/platforms/${platform}/arm-none-eabi.cmake" "-DCMAKE_BUILD_TYPE=Release")
+            options+=("-DCMAKE_TOOLCHAIN_FILE=examples/platforms/${platform}/arm-none-eabi.cmake" "-DCMAKE_BUILD_TYPE=MinSizeRel")
             ;;
         cc1352 | cc2538 | cc2652 | qpg6095 | samr21)
-            options+=("-DCMAKE_TOOLCHAIN_FILE=examples/platforms/${platform}/arm-none-eabi.cmake" "-DCMAKE_BUILD_TYPE=Release")
+            options+=("-DCMAKE_TOOLCHAIN_FILE=examples/platforms/${platform}/arm-none-eabi.cmake" "-DCMAKE_BUILD_TYPE=MinSizeRel")
             ;;
         *)
             options+=("-DCMAKE_TOOLCHAIN_FILE=examples/platforms/${platform}/arm-none-eabi.cmake")