Broken build system (idf v4.2)

[happyme531]

I just want to use serial GDB stub and himem, so I tried to rebuild the arduino lib, but seems the build system is broken

1. .`/build.sh prints:

make[4]: *** No targets specified and no makefile found.  Stop. 
make[3]: *** [CMakeFiles/bootloader.dir/build.make:112: bootloader-prefix/src/bootloader-stamp/bootloader-build] Error 2        make[2]: *** [CMakeFiles/Makefile2:2315: CMakeFiles/bootloader.dir/all] Error 2                                                
make[1]: *** [CMakeFiles/Makefile2:2185: CMakeFiles/idf-libs.dir/rule] Error 2                                                  
make: *** [Makefile:164: idf-libs] Error 2                      
command "idf-libs" is not known to idf.py and is not a Unix Makefiles target

2. After changing the "idf.py idf-libs" to "idf.py build", it can compile successfully, but then stuck in a infinite loop.

bash -x ./tools/prepare-libs.sh

+ for item in "$@"                                             
+ [[ /mnt/dev/home/user/esparduino/esp32-arduino-lib-builder/main != /mnt/dev/home/user/esparduino/esp32-arduino-lib-builder ]]
+ ipath=/mnt/dev/home/user/esparduino/esp32-arduino-lib-builder/main                                                           
++ basename /mnt/dev/home/user/esparduino/esp32-arduino-lib-builder/main                                                       
+ fname=main                                                   
+++ dirname /mnt/dev/home/user/esparduino/esp32-arduino-lib-builder/main                                                       
++ basename /mnt/dev/home/user/esparduino/esp32-arduino-lib-builder                                                            
+ dname=esp32-arduino-lib-builder                              
+ [[ esp32-arduino-lib-builder != \c\o\m\p\o\n\e\n\t\s ]]      
+ [[ esp32-arduino-lib-builder != \b\u\i\l\d ]]                
++ dirname /mnt/dev/home/user/esparduino/esp32-arduino-lib-builder/main                                                        
+ ipath=/mnt/dev/home/user/esparduino/esp32-arduino-lib-builder
++ basename /mnt/dev/home/user/esparduino/esp32-arduino-lib-builder                                                            
+ fname=esp32-arduino-lib-builder                              
+++ dirname /mnt/dev/home/user/esparduino/esp32-arduino-lib-builder                                                            
++ basename /mnt/dev/home/user/esparduino                      
+ dname=esparduino                                             
+ [[ esparduino != \c\o\m\p\o\n\e\n\t\s ]]                     
+ [[ esparduino != \b\u\i\l\d ]]                               
++ dirname /mnt/dev/home/user/esparduino/esp32-arduino-lib-builder                                                             
+ ipath=/mnt/dev/home/user/esparduino                          
++ basename /mnt/dev/home/user/esparduino                      
+ fname=esparduino                                             
+++ dirname /mnt/dev/home/user/esparduino                      
++ basename /mnt/dev/home/user                                 
+ dname=user                                                   
+ [[ user != \c\o\m\p\o\n\e\n\t\s ]]                           
+ [[ user != \b\u\i\l\d ]]                                     
++ dirname /mnt/dev/home/user/esparduino                       
+ ipath=/mnt/dev/home/user                                     
++ basename /mnt/dev/home/user                                 
+ fname=user                                                   
+++ dirname /mnt/dev/home/user                                 
++ basename /mnt/dev/home                                      
+ dname=home                                                   
+ [[ home != \c\o\m\p\o\n\e\n\t\s ]]                           
+ [[ home != \b\u\i\l\d ]]                                     
++ dirname /mnt/dev/home/user                                  
+ ipath=/mnt/dev/home                                          
++ basename /mnt/dev/home                                      
+ fname=home                                                   
+++ dirname /mnt/dev/home                                      
++ basename /mnt/dev                                           
+ dname=dev                                                    
+ [[ dev != \c\o\m\p\o\n\e\n\t\s ]]                            
+ [[ dev != \b\u\i\l\d ]]                                      
++ dirname /mnt/dev/home                                       
+ ipath=/mnt/dev                                               
++ basename /mnt/dev                                           
+ fname=dev                                                    
+++ dirname /mnt/dev                                           
++ basename /mnt                                               
+ dname=mnt                                                    
+ [[ mnt != \c\o\m\p\o\n\e\n\t\s ]]                            
+ [[ mnt != \b\u\i\l\d ]]                                      
++ dirname /mnt/dev                                            
+ ipath=/mnt                                                   
++ basename /mnt                                               
+ fname=mnt                                                    
+++ dirname /mnt                                               
++ basename /                                                  
+ dname=/           
+ [[ / != \c\o\m\p\o\n\e\n\t\s ]]                            
+ [[ / != \b\u\i\l\d ]]                                      
++ dirname /                                            
+ ipath=/                                                   
++ basename /                                              
+ fname=/                                                  
+++ dirname /                                               
++ basename /                                                  
+ dname=/           

[me-no-dev]

you must have missed something while pulling the repo. idf.py idf-libs is defined here: https://github.com/espressif/esp32-arduino-lib-builder/blob/release/v4.2/CMakeLists.txt#L12-L18