This time I upgraded xcode 12.3 -> 13.1. The project code is c/c++ library code. When compiling after upgrade, basic system header files such as errno.h and unistd.h, string.h ... cannot be referenced.
The code uses c api a lot instead of c++ api. (std::string -> char *, memcpy, memset etc.) How to solve it? must upgrade because of iPhone live debugging.
env os : monterey 12.0.1 xcode : 13.1
error message: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1/string.h:73:64: Use of undeclared identifier 'strchr' /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1/stdlib.h:148:12: No member named 'lldiv' in the global namespace /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1/string.h:80:75: Use of undeclared identifier 'strpbrk' /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1/string.h:94:76: Use of undeclared identifier 'memchr' ...