提示未定义__rtmsymtab_start与__rtmsymtab_end

发布于 2021-11-18 23:12:27 浏览：1223 订阅该版

我在编译micropython时提示的错误如下：
```
> scons -j 4                                                                                              
scons: Reading SConscript files ...                                                                       
scons: done reading SConscript files.                                                                     
                                                                                                          
scons: warning: you do not seem to have the pywin32 extensions installed;                                 
        parallel (-j) builds may not work reliably with open Python files.                                
File "D:\rt-thread\env\tools\Python27\Scripts\scons.py", line 204, in <module>                            
scons: Building targets ...                                                                               
scons: building associated VariantDir targets: build                                                      
LINK rt-thread.elf                                                                                        
build\kernel\components\libc\libdl\dlmodule.o: In function `rt_system_dlmodule_init':                     
D:\rt-thread\RTOS_SDK\components\libc\libdl/dlmodule.c:825: undefined reference to `__rtmsymtab_start'    
D:\rt-thread\RTOS_SDK\components\libc\libdl/dlmodule.c:825: undefined reference to `__rtmsymtab_end'      
collect2.exe: error: ld returned 1 exit status                                                            
scons: *** [rt-thread.elf] Error 1                                                                        
scons: building terminated because of errors.     
```
我不知道是启动了micropython的哪个功能启动了libc的编译导致了这个问题。
必须在board\linker_scripts\link.ids中添加如下代码才能编译通过：
```
/* section information for modules */
. = ALIGN(4);
__rtmsymtab_start = .;
KEEP(*(RTMSymTab))
__rtmsymtab_end = .;
```
但是这句话为什么原始的bsp中没有，为什么要加，加了会有什么效果呢？