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是否可以将ESP8266与Arduino封装一起使用map？

这是我的代码：

#include <map>

typedef std::map<int, int> Items;

void setup() {
  Items items;
  items[2]=5;
  //items.emplace(4,5);
}

void loop() {

}

这是编译/链接错误：

Arduino: 1.6.5 (Windows 8.1), Board: "Generic ESP8266 Module, Serial, 80 MHz, 40MHz, DIO, 115200, 512K (64K SPIFFS)"

sketch_oct31a.cpp.o: In function `loop':
C:\Program Files (x86)\Arduino/sketch_oct31a.ino:11: undefined reference to     `std::_Rb_tree_insert_and_rebalance(bool, std::_Rb_tree_node_base*,     std::_Rb_tree_node_base*, std::_Rb_tree_node_base&)'
sketch_oct31a.cpp.o: In function `_M_emplace_hint_unique<const     std::piecewise_construct_t&, std::tuple<int&&>, std::tuple<> >':
c:\users\user\appdata\roaming\arduino15\packages\esp8266\tools\xtensa-lx106-    elf-gcc\1.20.0-26-gb404fb9-2\xtensa-lx106-    elf\include\c++\4.8.2\bits/stl_tree.h:1673: undefined reference to     `std::_Rb_tree_insert_and_rebalance(bool, std::_Rb_tree_node_base*,     std::_Rb_tree_node_base*, std::_Rb_tree_node_base&)'
sketch_oct31a.cpp.o: In function `std::_Rb_tree<int, std::pair<int const,     int>, std::_Select1st<std::pair<int const, int> …

我写了一个小程序来显示相对于GMT(或UTC)的当地时间:

struct tm l;    
time_t stamp = 1534435540;

// No TZ set
printf("TZ=%s\n",getenv("TZ"));
gmtime_r(&stamp, &l);
printf("UTC: %0u:%0u:%0u - %0u.%0u.%0u\n",l.tm_hour,l.tm_min,l.tm_sec,l.tm_mday,l.tm_mon+1,l.tm_year+1900);
localtime_r(&stamp, &l);
printf("Local: %0u:%0u:%0u - %0u.%0u.%0u\n\n",l.tm_hour,l.tm_min,l.tm_sec,l.tm_mday,l.tm_mon+1,l.tm_year+1900);

// Positive TZ: east to Greenwich (e.g. China)
setenv("TZ", "UTC+6:00", 1);    
printf("TZ=%s\n",getenv("TZ"));     
tzset();    
gmtime_r(&stamp, &l);
printf("UTC: %0u:%0u:%0u - %0u.%0u.%0u\n",l.tm_hour,l.tm_min,l.tm_sec,l.tm_mday,l.tm_mon+1,l.tm_year+1900);
localtime_r(&stamp, &l);
printf("Local: %0u:%0u:%0u - %0u.%0u.%0u\n\n",l.tm_hour,l.tm_min,l.tm_sec,l.tm_mday,l.tm_mon+1,l.tm_year+1900);

// Negative TZ: west to Greenwich (e.g. US/Canada)
setenv("TZ", "UTC-6:00", 1);    
printf("TZ=%s\n",getenv("TZ"));
tzset();    
gmtime_r(&stamp, &l);
printf("UTC: %0u:%0u:%0u - %0u.%0u.%0u\n",l.tm_hour,l.tm_min,l.tm_sec,l.tm_mday,l.tm_mon+1,l.tm_year+1900);
localtime_r(&stamp, &l);
printf("Local: %0u:%0u:%0u - %0u.%0u.%0u\n\n",l.tm_hour,l.tm_min,l.tm_sec,l.tm_mday,l.tm_mon+1,l.tm_year+1900);

该计划的输出如下:

TZ=<null>
UTC: 16:5:40 - …