After the Update of Latest Command Line Tools 16.3 I am facing issue to compile C++ programs. Like it is giving some kind of library error in the MACOSX15.sdk file and this is the error. In file included from /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/mach/machine/_structs.h:35, from /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/arm/_mcontext.h:36, from /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/machine/_mcontext.h:34, from /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/sys/signal.h:146, from /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/sys/wait.h:109, from /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/_stdlib.h:70, from /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/stdlib.h:58, from /opt/homebrew/Cellar/gcc/14.2.0_1/include/c++/14/cstdlib:79, from /opt/homebrew/Cellar/gcc/14.2.0_1/include/c++/14/stdlib.h:36, from /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/assert.h:44, from /opt/homebrew/Cellar/gcc/14.2.0_1/include/c++/14/cassert:44, from /opt/homebrew/Cellar/gcc/14.2.0_1/include/c++/14/aarch64-apple-darwin24/bits/stdc++.h:33, from 1.cpp:1: /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/mach/arm/_structs.h:627:35: error: expected primary-expression before 'unsigned' 627 | } __attribute__((aligned(_Alignof(unsigned int)))); | ^~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/mach/arm/_structs.h:627:26: error: '_Alignof' was not declared in this scope 627 | } __attribute__((aligned(_Alignof(unsigned int)))); | ^~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/mach/arm/_structs.h:633:35: error: expected primary-expression before 'unsigned' 633 | } __attribute__((aligned(_Alignof(unsigned int)))); | ^~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/mach/arm/_structs.h:633:26: error: '_Alignof' was not declared in this scope 633 | } __attribute__((aligned(_Alignof(unsigned int)))); | ^~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/mach/arm/_structs.h:639:35: error: expected primary-expression before 'unsigned' 639 | } __attribute__((aligned(_Alignof(unsigned int)))); | ^~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/mach/arm/_structs.h:639:26: error: '_Alignof' was not declared in this scope 639 | } __attribute__((aligned(_Alignof(unsigned int)))); | ^~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/mach/arm/_structs.h:645:35: error: expected primary-expression before 'unsigned' 645 | } __attribute__((aligned(_Alignof(unsigned int)))); | ^~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk/usr/include/mach/arm/_structs.h:645:26: error: '_Alignof' was not declared in this scope 645 | } __attribute__((aligned(_Alignof(unsigned int)))); But after downgrading the version to 16.2 it works fine. I can't understand that it's their any issue with Command Line Tools 16.3??