[update] support armclang and c++11.

components/cplusplus/cpp11/README.md

@@ -0,0 +1,49 @@
+# C++ 11 support for RT-Thread
+
+## Features
+
+Here are some features about rt-thread c++11 threading futures.
+
+- Atomic.
+- Conditional variables.
+- Clocks.
+- Future.
+- Mutexes.
+- Threads.
+- TLS.
+
+## How To Use
+
+Note that using C++ 11 in rt-thread requires modifying some of the files in the toolchain. Before modifying the tool, back up the tool chain.  
+
+1. Enable c++11 support
+
+   ![](figures/Snipaste_2021-09-02_16-00-09.png)
+
+2. Download toolchain GCC 10.2.1:
+
+   ```shell
+   gcc version 10.2.1 20201103 (release) (GNU Arm Embedded Toolchain 10-2020-q4-major)
+   ```
+
+3. Delete the following files:
+
+   ```shell
+   rm -f toolchain/arm-none-eabi/include/c++/10.2.1/thread
+   rm -f toolchain/arm-none-eabi/include/c++/10.2.1/mutex
+   rm -f toolchain/arm-none-eabi/include/c++/10.2.1/condition_variable
+   rm -f toolchain/arm-none-eabi/include/c++/10.2.1/future
+   rm -f toolchain/arm-none-eabi/include/pthread.h
+   ```
+
+4. Clear the contents of the following files and keep them to prevent compilation failures:
+
+   ```shell
+   toolchain/arm-none-eabi/include/sys/_pthreadtypes.h
+   ```
+   
+5. Update `rtconfig.py` file. add compilation parameters:
+
+   ```shell
+   CXXFLAGS = CFLAGS  + ' -std=c++11 -fabi-version=0 -MMD -MP -MF'
+   ```

components/cplusplus/cpp11/README_ZH.md

@@ -0,0 +1,48 @@
+# cpp 11 support for rt-thread
+
+## 特性
+
+下面是 RT-Thread 支持的 C++ 11 线程特性。
+
+- Atomic.
+- Conditional variables.
+- Clocks.
+- Future.
+- Mutexes.
+- Threads.
+- TLS.
+
+## 如何使用
+
+请注意，在 RT-Thread 中使用 C++ 11，需要修改工具链中的部分文件。请在修改之前，备份好工具链。
+
+1. 使能 c++11
+   ![](figures/Snipaste_2021-09-02_16-00-09.png)
+
+2. 下载 GCC 工具链
+
+   ```shell
+   gcc version 10.2.1 20201103 (release) (GNU Arm Embedded Toolchain 10-2020-q4-major)
+   ```
+
+3. 删除下面的文件
+
+   ```shell
+   rm -f toolchain/arm-none-eabi/include/c++/10.2.1/thread
+   rm -f toolchain/arm-none-eabi/include/c++/10.2.1/mutex
+   rm -f toolchain/arm-none-eabi/include/c++/10.2.1/condition_variable
+   rm -f toolchain/arm-none-eabi/include/c++/10.2.1/future
+   rm -f toolchain/arm-none-eabi/include/pthread.h
+   ```
+
+4. 请清除下面文件的内容，保留文件避免编译失败
+
+   ```shell
+   toolchain/arm-none-eabi/include/sys/_pthreadtypes.h
+   ```
+
+5. 更新 `rtconfig.py` 文件，添加 c++ 编译参数:
+
+   ```shell
+   CXXFLAGS = CFLAGS  + ' -std=c++11 -fabi-version=0 -MMD -MP -MF'
+   ```

components/cplusplus/cpp11/armclang/clock.cpp

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include <arm-tpl.h>
+#include <sys/time.h>
+#include <rtthread.h>
+
+extern "C" int __ARM_TPL_clock_realtime(__ARM_TPL_timespec_t* __ts)
+{
+    unsigned int t = std::time(nullptr);
+    __ts->tv_sec = t;
+    __ts->tv_nsec = 0;
+    return 0;
+}
+
+extern "C" int __ARM_TPL_clock_monotonic(__ARM_TPL_timespec_t* __ts)
+{
+    unsigned int t = rt_tick_get();
+    __ts->tv_sec = t / RT_TICK_PER_SECOND;
+    __ts->tv_nsec = (t %RT_TICK_PER_SECOND) * NANOSECOND_PER_TICK  ;
+    return 0;
+}

components/cplusplus/cpp11/armclang/condvar.cpp

@@ -0,0 +1,178 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include <arm-tpl.h>
+#include "tpl.h"
+#include <new>
+#include <cstdint>
+#include <stdatomic.h>
+
+arm_tpl_cv::arm_tpl_cv()
+{
+    s = rt_sem_create("semxs", 0, RT_IPC_FLAG_PRIO);
+    if (s == nullptr)
+        RT_ASSERT(0);
+    h = rt_sem_create("semxh", 0, RT_IPC_FLAG_PRIO);
+    if (h == nullptr)
+    {
+        rt_sem_delete(s);
+        RT_ASSERT(0);
+    }
+    x = rt_mutex_create("mutx", RT_IPC_FLAG_PRIO);
+    if (x == nullptr)
+    {
+        rt_sem_delete(s);
+        rt_sem_delete(h);
+        RT_ASSERT(0);
+    }
+}
+
+arm_tpl_cv::~arm_tpl_cv()
+{
+    rt_mutex_delete(x);
+    rt_sem_delete(h);
+    rt_sem_delete(s);
+}
+
+void arm_tpl_cv::wait(rt_mutex_t lock, bool recursive)
+{
+    while (rt_mutex_take(x, ARM_TPL_MAX_DELAY) != 0);
+    rt_sem_release(s);
+    rt_mutex_release(x);
+    if (recursive)
+        rt_mutex_release(lock);
+    else
+        rt_mutex_release(lock);
+    while (rt_sem_take(h, ARM_TPL_MAX_DELAY) != 0);
+    if (recursive)
+        while (rt_mutex_take(lock, ARM_TPL_MAX_DELAY) != 0);
+    else
+        while (rt_mutex_take(lock, ARM_TPL_MAX_DELAY) != 0);
+}
+
+int arm_tpl_cv::timedwait(rt_mutex_t lock, bool recursive, unsigned int timeout_ms)
+{
+    int result = 0;
+    while (rt_mutex_take(x, ARM_TPL_MAX_DELAY) != 0);
+    rt_sem_release(s);
+    rt_mutex_release(x);
+    if (recursive)
+        rt_mutex_release(lock);
+    else
+        rt_mutex_release(lock);
+    if (rt_sem_take(h, rt_tick_from_millisecond(timeout_ms)) != 0)
+    {
+        while (rt_mutex_take(x, ARM_TPL_MAX_DELAY) != 0);
+        if (rt_sem_take(h, 0) != 0)
+        {
+            if (rt_sem_take(s, 0) != 0)
+                result = -1;
+            else
+                result = 1;
+        }
+        rt_mutex_release(x);
+    }
+    if (recursive)
+        while (rt_mutex_take(lock, ARM_TPL_MAX_DELAY) != 0);
+    else
+        while (rt_mutex_take(lock, ARM_TPL_MAX_DELAY) != 0);
+    return result;
+}
+
+void arm_tpl_cv::signal()
+{
+    while (rt_mutex_take(x, ARM_TPL_MAX_DELAY) != 0);
+    if (rt_sem_take(s, 0) == 0)
+        rt_sem_release(h);
+    rt_mutex_release(x);
+}
+
+void arm_tpl_cv::broadcast()
+{
+    while (rt_mutex_take(x, ARM_TPL_MAX_DELAY) != 0);
+    auto count = s->value;
+    for (auto i = 0; i < count; i++)
+    {
+        while (rt_sem_take(s, ARM_TPL_MAX_DELAY) != 0);
+        rt_sem_release(h);
+    }
+    rt_mutex_release(x);
+}
+
+static int check_create(volatile __ARM_TPL_condvar_t *__vcv)
+{
+    if (__vcv->data == 0)
+    {
+        uintptr_t cv_new;
+        cv_new = reinterpret_cast<uintptr_t>(new arm_tpl_cv());
+        if (cv_new == 0)
+        {
+            return -1;
+        }
+        uintptr_t cv_null = 0;
+        if (!atomic_compare_exchange_strong(&__vcv->data, &cv_null, cv_new))
+            delete reinterpret_cast<arm_tpl_cv *>(cv_new);
+    }
+    return 0;
+}
+
+extern "C" int __ARM_TPL_condvar_wait(__ARM_TPL_condvar_t *__cv, __ARM_TPL_mutex_t *__m)
+{
+    volatile __ARM_TPL_condvar_t *__vcv = __cv;
+    if (check_create(__vcv) != 0)
+        return -1;
+    struct arm_tpl_mutex_struct *tmutex = (struct arm_tpl_mutex_struct *)(__m->data);
+    ((arm_tpl_cv *) __vcv->data)->wait(tmutex->mutex, tmutex->type == RECURSIVE);
+    return 0;
+}
+
+extern "C" int __ARM_TPL_condvar_timedwait(__ARM_TPL_condvar_t *__cv,
+                                __ARM_TPL_mutex_t *__m,
+                                __ARM_TPL_timespec_t *__ts)
+{
+    volatile __ARM_TPL_condvar_t *__vcv = __cv;
+    if (check_create(__vcv) != 0)
+        return -1;
+    __ARM_TPL_timespec_t now;
+    if (__ARM_TPL_clock_realtime(&now) != 0)
+        return -1;
+    struct arm_tpl_mutex_struct *tmutex = (struct arm_tpl_mutex_struct *)(__m->data);
+    unsigned int timeout_ms = (__ts->tv_sec - now.tv_sec) * 1000 + (__ts->tv_nsec - now.tv_nsec) / 1000000;
+    if (((arm_tpl_cv *) __vcv->data)->timedwait(tmutex->mutex, tmutex->type == RECURSIVE, timeout_ms) < 0)
+        return -1;
+    return 0;
+}
+
+extern "C" int __ARM_TPL_condvar_signal(__ARM_TPL_condvar_t *__cv)
+{
+    volatile __ARM_TPL_condvar_t *__vcv = __cv;
+    if (__vcv->data != 0)
+        ((arm_tpl_cv *) __vcv->data)->signal();
+    return 0;
+}
+
+extern "C" int __ARM_TPL_condvar_broadcast(__ARM_TPL_condvar_t *__cv)
+{
+    volatile __ARM_TPL_condvar_t *__vcv = __cv;
+    if (__vcv->data != 0)
+        ((arm_tpl_cv *) __vcv->data)->broadcast();
+    return 0;
+}
+
+extern "C" int __ARM_TPL_condvar_destroy(__ARM_TPL_condvar_t *__cv)
+{
+    volatile __ARM_TPL_condvar_t *__vcv = __cv;
+    if (__vcv->data != 0)
+    {
+        delete (arm_tpl_cv *) __vcv->data;
+        __vcv->data = 0;
+    }
+    return 0;
+}

components/cplusplus/cpp11/armclang/miscellaneous.cpp

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include <arm-tpl.h>
+
+extern "C" int __ARM_TPL_execute_once(__ARM_TPL_exec_once_flag *__flag,
+                                      void (*__init_routine)(void))
+{
+    if (*__flag == 0)
+    {
+        __init_routine();
+        *__flag = 1;
+    }
+    return 0;
+}

components/cplusplus/cpp11/armclang/mutex.cpp

@@ -0,0 +1,108 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include <arm-tpl.h>
+#include <cstdint>
+#include <stdatomic.h>
+#include "tpl.h"
+
+static int check_create(volatile __ARM_TPL_mutex_t *__vm, bool recursive = false)
+{
+    if (__vm->data == 0)
+    {
+        uintptr_t mut_null = 0;
+        arm_tpl_mutex_struct *mutex_p = (arm_tpl_mutex_struct *)rt_malloc(sizeof(arm_tpl_mutex_struct));
+        if (mutex_p == nullptr) return -1;
+
+        if (recursive)
+            mutex_p->mutex = rt_mutex_create("mutexx", RT_IPC_FLAG_PRIO);
+        else
+            mutex_p->mutex = rt_mutex_create("mutexx", RT_IPC_FLAG_PRIO);
+
+        if (mutex_p->mutex == nullptr)
+        {
+            rt_free(mutex_p);
+            return -1;
+        }
+        mutex_p->type = recursive ? RECURSIVE : NORMAL;
+        uintptr_t mut_new = reinterpret_cast<uintptr_t>(mutex_p);
+        if (!atomic_compare_exchange_strong(&__vm->data, &mut_null, mut_new))
+        {
+            rt_mutex_delete(mutex_p->mutex);
+            rt_free(mutex_p);
+        }
+    }
+    return 0;
+}
+
+static int mutexLock(arm_tpl_mutex_struct *mutex_p, rt_tick_t timeOut)
+{
+    if (mutex_p->type == RECURSIVE)
+    {
+        if (rt_mutex_take(mutex_p->mutex, timeOut) == 0)
+            return 0;
+    }
+    else
+    {
+        if (rt_mutex_take(mutex_p->mutex, timeOut) == 0)
+            return 0;
+    }
+    return -1;
+}
+
+static int mutexUnlock(arm_tpl_mutex_struct *mutex_p)
+{
+    if (mutex_p->type == RECURSIVE)
+        rt_mutex_release(mutex_p->mutex);
+    else
+        rt_mutex_release(mutex_p->mutex);
+    return 0;
+}
+
+extern "C" int __ARM_TPL_recursive_mutex_init(__ARM_TPL_mutex_t *__m)
+{
+    volatile __ARM_TPL_mutex_t *__vm = __m;
+    return check_create(__vm, true);
+}
+
+extern "C" int __ARM_TPL_mutex_lock(__ARM_TPL_mutex_t *__m)
+{
+    volatile __ARM_TPL_mutex_t *__vm = __m;
+    if (check_create(__vm))
+        return -1;
+    while (mutexLock((arm_tpl_mutex_struct *)(__vm->data), ARM_TPL_MAX_DELAY) != 0);
+    return 0;
+}
+
+extern "C" int __ARM_TPL_mutex_trylock(__ARM_TPL_mutex_t *__m)
+{
+    volatile __ARM_TPL_mutex_t *__vm = __m;
+    if (check_create(__vm))
+        return -1;
+    return mutexLock((arm_tpl_mutex_struct *)(__vm->data), 0);
+}
+
+extern "C" int __ARM_TPL_mutex_unlock(__ARM_TPL_mutex_t *__m)
+{
+    volatile __ARM_TPL_mutex_t *__vm = __m;
+    return mutexUnlock((arm_tpl_mutex_struct *)(__vm->data));
+}
+
+extern "C" int __ARM_TPL_mutex_destroy(__ARM_TPL_mutex_t *__m)
+{
+    volatile __ARM_TPL_mutex_t *__vm = __m;
+    if (__vm->data != 0)
+    {
+        rt_mutex_delete(((arm_tpl_mutex_struct *)(__vm->data))->mutex);
+        rt_free((void *)(__vm->data));
+        __vm->data = 0;
+    }
+    return 0;
+}

components/cplusplus/cpp11/armclang/thread.cpp

@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include <arm-tpl.h>
+#include "tpl.h"
+#include <cstdio>
+#include <pthread.h>
+
+extern "C" int __ARM_TPL_thread_create(__ARM_TPL_thread_t *__t,
+                                       void *(*__func)(void *),
+                                       void *__arg)
+{
+    int ret = 0;
+    /* TODO memory leek */
+    pthread_t *pid = (pthread_t *)rt_malloc(sizeof(pthread_t));
+    if (pid == nullptr)
+        return -1;
+    ret = pthread_create(pid, RT_NULL, __func, __arg);
+    if (ret == 0)
+    {
+        __t->data = (std::uintptr_t)pid;
+        return 0;
+    }
+    return -1;
+}
+
+extern "C" int __ARM_TPL_thread_id_compare(__ARM_TPL_thread_id __tid1,
+        __ARM_TPL_thread_id __tid2)
+{
+    if (__tid1 > __tid2)
+        return 1;
+    else if (__tid1 < __tid2)
+        return -1;
+    else
+        return 0;
+}
+
+extern "C" __ARM_TPL_thread_id __ARM_TPL_thread_get_current_id()
+{
+    return (__ARM_TPL_thread_id)pthread_self();
+}
+
+extern "C" __ARM_TPL_thread_id __ARM_TPL_thread_get_id(
+    const __ARM_TPL_thread_t *__t)
+{
+    return (__ARM_TPL_thread_id)((*(pthread_t *)__t->data));
+}
+
+extern "C" int __ARM_TPL_thread_join(__ARM_TPL_thread_t *__t)
+{
+    pthread_join((*(pthread_t *)__t->data), RT_NULL);
+    return 0;
+}
+
+extern "C" int __ARM_TPL_thread_detach(__ARM_TPL_thread_t *__t)
+{
+    pthread_detach((*(pthread_t *)__t->data));
+    return 0;
+}
+
+extern "C" void __ARM_TPL_thread_yield()
+{
+    rt_thread_yield();
+}
+
+extern "C" int __ARM_TPL_thread_nanosleep(const __ARM_TPL_timespec_t *__req,
+        __ARM_TPL_timespec_t *__rem)
+{
+    return nanosleep(__req, rem);
+}
+
+extern "C" unsigned __ARM_TPL_thread_hw_concurrency()
+{
+    return 1;
+}
+
+extern "C" int __ARM_TPL_tls_create(__ARM_TPL_tls_key *__key,
+                                    void (*__at_exit)(void *))
+{
+    pthread_key_t key; 
+    
+    if (pthread_key_create(&key, __at_exit) == 0)
+    {
+        *__key = key;
+        return 0;
+    }
+    return -1;
+}
+
+extern "C" void *__ARM_TPL_tls_get(__ARM_TPL_tls_key __key)
+{
+    return pthread_getspecific(__key);
+}
+
+extern "C" int __ARM_TPL_tls_set(__ARM_TPL_tls_key __key, void *__p)
+{
+    if (pthread_setspecific(__key, (void*)__p) != 0)
+    {
+        return -1;
+    }
+    return 0;
+}

components/cplusplus/cpp11/armclang/tpl.h

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#pragma once
+#ifndef __cplusplus
+void ARMTPLInit();
+#else
+#include <rtthread.h>
+
+#define ARM_TPL_MAX_DELAY 1000
+#define ARM_TPL_THREAD_STACK_SIZE 4096
+
+enum arm_tpl_mutex_type
+{
+    NORMAL,
+    RECURSIVE,
+};
+
+struct arm_tpl_mutex_struct
+{
+    rt_mutex_t mutex;
+    arm_tpl_mutex_type type;
+};
+
+struct arm_tpl_thread_struct
+{
+    rt_thread_t task;
+    void *(*func)(void *);
+    void *arg;
+    rt_sem_t join_sem;
+    rt_sem_t detach_sem;
+};
+
+class arm_tpl_cv
+{
+public:
+    arm_tpl_cv();
+    ~arm_tpl_cv();
+    void wait(rt_mutex_t lock, bool recursive);
+    int timedwait(rt_mutex_t lock, bool recursive, unsigned int timeout_ms);
+    void signal();
+    void broadcast();
+private:
+    rt_sem_t s;
+    rt_sem_t h;
+    rt_mutex_t x;
+};
+
+#endif

components/cplusplus/cpp11/atomic_8.c

@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     peterfan     Add copyright header.
+ */
+
+#include <rthw.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+/*
+* override gcc builtin atomic function for std::atomic<int64_t>, std::atomic<uint64_t>
+* @see https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html
+*/
+uint64_t __atomic_load_8(volatile void *ptr, int memorder)
+{
+    volatile uint64_t *val_ptr = (volatile uint64_t *)ptr;
+    register rt_base_t level;
+    uint64_t tmp;
+    level = rt_hw_interrupt_disable();
+    tmp = *val_ptr;
+    rt_hw_interrupt_enable(level);
+    return tmp;
+}
+
+void __atomic_store_8(volatile void *ptr, uint64_t val, int memorder)
+{
+    volatile uint64_t *val_ptr = (volatile uint64_t *)ptr;
+    register rt_base_t level;
+    level = rt_hw_interrupt_disable();
+    *val_ptr = val;
+    rt_hw_interrupt_enable(level);
+}
+
+uint64_t __atomic_exchange_8(volatile void *ptr, uint64_t val, int memorder)
+{
+    volatile uint64_t *val_ptr = (volatile uint64_t *)ptr;
+    register rt_base_t level;
+    uint64_t tmp;
+    level = rt_hw_interrupt_disable();
+    tmp = *val_ptr;
+    *val_ptr = val;
+    rt_hw_interrupt_enable(level);
+    return tmp;
+}
+
+bool __atomic_compare_exchange_8(volatile void *ptr, volatile void *expected, uint64_t desired, bool weak, int success_memorder, int failure_memorder)
+{
+    volatile uint64_t *val_ptr = (volatile uint64_t *)ptr;
+    volatile uint64_t *expected_ptr = (volatile uint64_t *)expected;
+    register rt_base_t level;
+    bool exchanged;
+    level = rt_hw_interrupt_disable();
+    if (*val_ptr == *expected_ptr)
+    {
+        *val_ptr = desired;
+        exchanged = true;
+    }
+    else
+    {
+        *expected_ptr = *val_ptr;
+        exchanged = false;
+    }
+    rt_hw_interrupt_enable(level);
+    return exchanged;
+}
+
+#define __atomic_fetch_op_8(OPNAME, OP) \
+uint64_t __atomic_fetch_##OPNAME##_8(volatile void *ptr, uint64_t val, int memorder) {\
+    volatile uint64_t* val_ptr = (volatile uint64_t*)ptr;\
+    register rt_base_t level;\
+    uint64_t tmp;\
+    level = rt_hw_interrupt_disable();\
+    tmp = *val_ptr;\
+    *val_ptr OP##= val;\
+    rt_hw_interrupt_enable(level);\
+    return tmp;\
+}
+
+__atomic_fetch_op_8(add, +)
+__atomic_fetch_op_8(sub, -)
+__atomic_fetch_op_8( and, &)
+__atomic_fetch_op_8( or, |)
+__atomic_fetch_op_8(xor, ^)

components/cplusplus/cpp11/gcc/__utils.h

@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#pragma once
+
+#include <cstdlib>
+#include <system_error>
+#include <chrono>
+#include <ratio>
+
+#include <rtthread.h>
+
+#define RT_USING_CPP_EXCEPTION
+
+inline void throw_system_error(int err, const char *what_msg)
+{
+#ifdef RT_USING_CPP_EXCEPTION
+    throw std::system_error(std::error_code(err, std::system_category()), what_msg);
+#else
+    (void)err;
+    (void)what_msg;
+    ::abort();
+#endif
+}
+
+class tick_clock
+{
+public:
+    typedef clock_t rep;
+    typedef std::ratio<1, RT_TICK_PER_SECOND> period;
+
+    typedef std::chrono::duration<tick_clock::rep, tick_clock::period> duration;
+    typedef std::chrono::time_point<tick_clock> time_point;
+
+    constexpr static bool is_ready = true;
+
+    static time_point now();
+};
+
+class real_time_clock
+{
+public:
+    typedef std::chrono::nanoseconds duration;
+    typedef duration::rep rep;
+    typedef duration::period period;
+    typedef std::chrono::time_point<real_time_clock, duration> time_point;
+
+    static constexpr bool is_steady = true;
+
+    static time_point
+    now() noexcept;
+};

components/cplusplus/cpp11/gcc/condition_variable.cpp

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include "condition_variable"
+
+namespace std
+{
+    void condition_variable::wait(unique_lock<mutex>& lock)
+    {
+        int err = pthread_cond_wait(&_m_cond, lock.mutex()->native_handle());
+
+        if (err)
+        {
+            throw_system_error(err, "condition_variable::wait: failed to wait on a condition");
+        }
+    }
+
+    void notify_all_at_thread_exit(condition_variable& cond, unique_lock<mutex> lk)
+    {
+        // TLS currently not available
+        mutex* mut = lk.release();
+        mut->unlock();
+        cond.notify_all();
+    }
+
+
+} // namespace std

components/cplusplus/cpp11/gcc/mutex.cpp

@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include "mutex"
+
+namespace std
+{
+    // use a set of global and static objects
+    // a proxy function to pthread_once
+
+    function<void()> once_functor;
+
+    mutex& get_once_mutex()
+    {
+        static mutex once_mutex;
+        return once_mutex;
+    }
+
+    inline unique_lock<mutex>*& get_once_functor_lock_ptr()
+    {
+        static unique_lock<mutex>* once_functor_mutex_ptr = nullptr;
+        return once_functor_mutex_ptr;
+    }
+
+    void set_once_functor_lock_ptr(unique_lock<mutex>* m_ptr)
+    {
+        get_once_functor_lock_ptr() = m_ptr;
+    }
+
+    extern "C"  
+    {
+        void once_proxy()
+        {
+            // need to first transfer the functor's ownership so as to call it
+            function<void()> once_call = std::move(once_functor);
+
+            // no need to hold the lock anymore
+            unique_lock<mutex>* lock_ptr = get_once_functor_lock_ptr();            
+            get_once_functor_lock_ptr() = nullptr;
+            lock_ptr->unlock();
+
+            once_call();
+        }
+    }
+}

components/cplusplus/cpp11/gcc/thread.cpp

@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include "thread"
+#include "__utils.h"
+
+
+#define _RT_NPROCS 0
+
+namespace std
+{
+
+    extern "C"
+    {
+        static void* execute_native_thread_routine(void *p)
+        {
+            thread::invoker_base* t = static_cast<thread::invoker_base*>(p);
+            thread::invoker_base_ptr local;
+            local.swap(t->this_ptr); // tranfer the ownership of the invoker into the thread entry
+
+            local->invoke();
+
+            return NULL;
+        }
+    }
+
+    void thread::start_thread(invoker_base_ptr b)
+    {
+        auto raw_ptr = b.get();
+        // transfer the ownership of the invoker to the new thread
+        raw_ptr->this_ptr = std::move(b); 
+        int err = pthread_create(&_m_thr.__cpp_thread_t, NULL,
+                &execute_native_thread_routine, raw_ptr);
+
+        if (err) 
+        {
+            raw_ptr->this_ptr.reset();
+            throw_system_error(err, "Failed to create a thread");
+        }
+        
+    }    
+
+    thread::~thread()
+    {
+        if (joinable()) // when either not joined or not detached
+            terminate();
+    }
+
+    void thread::join()
+    {
+        int err = EINVAL;
+
+        if (joinable())
+            err = pthread_join(native_handle(), NULL);
+        
+        if (err) 
+        {
+            throw_system_error(err, "thread::join failed");
+        }
+    
+        _m_thr = id();
+    }
+
+    void thread::detach()
+    {
+        int err = EINVAL;
+
+        if (joinable())
+            err = pthread_detach(native_handle());
+        if (err)
+        {
+            throw_system_error(err, "thread::detach failed");
+        }
+    
+        _m_thr = id();
+    }
+
+    // TODO: not yet actually implemented.
+    // The standard states that the returned value should only be considered a hint.
+    unsigned thread::hardware_concurrency() noexcept 
+    {   
+        int __n = _RT_NPROCS;
+        if (__n < 0)
+            __n = 0;
+        return __n;
+    }
+}

components/cplusplus/cpp11/gcc/utils.cpp

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include "__utils.h"
+#include <sys/time.h>
+
+tick_clock::time_point tick_clock::now()
+{
+    tick_clock::rep cur_tk = clock();
+    tick_clock::duration cur_time(cur_tk);
+
+    return tick_clock::time_point(cur_time);
+}
+
+real_time_clock::time_point real_time_clock::now() noexcept
+{
+    timespec tp;
+    clock_gettime(CLOCK_REALTIME, &tp);
+
+    return time_point(duration(std::chrono::seconds(tp.tv_sec))
+                        + std::chrono::nanoseconds(tp.tv_nsec));
+}

components/cplusplus/cpp11/thread_local_impl.cpp

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2021-04-27     flybreak     the first version.
+ */
+
+#include <pthread.h>
+#include <cstdlib>
+
+typedef void (*destructor) (void *);
+
+extern "C"
+int __cxa_thread_atexit_impl(destructor dtor, void* obj, void* dso_symbol)
+{
+    pthread_key_t key_tmp;
+    if (pthread_key_create(&key_tmp, dtor) != 0)
+        abort();
+    pthread_setspecific(key_tmp, obj);
+    return 0;
+}
+
+#if defined(__GNUC__) && !defined(__ARMCC_VERSION)/*GCC*/
+#include <cxxabi.h>
+
+extern"C"
+int __cxxabiv1::__cxa_thread_atexit(destructor dtor, void *obj, void *dso_handle)
+{
+    return __cxa_thread_atexit_impl(dtor, obj, dso_handle);
+}
+#endif