Error in log is:
/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))));
| ^~~~~~~~
make[5]: *** [aarch64-apple-darwin24/bits/stdc++.h.gch/O2ggnu++0x.gch] Error 1
I found a corresponding Homebrew report but it just says it has already been fixed.
I believe the fix was this commit from this PR.
This seems to be a new problem caused by the macOS 15.4 SDK, so your macOS 11.3 SDK is evidently not being used here.
