Some problem with arm, is this a bug？

[cxwx1]

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╰─ root --version ─╯
ROOT Version: 6.35.01
Built for macosxarm64 on Dec 17 2024, 14:47:34
From heads/master@v6-35-01-555-g0beff5893a

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Dear all,
I’ve tried to compile astroROOT for new ROOT6 step by step.
First issue:

clang++ -Dcx_tf_container_EXPORTS -I/Users/chenxu/software/ROOT/install/include -I/Users/chenxu/software/chenxufunc/git/tools/astroROOT/tf_container -I/usr/local/include -m64 -pipe -fsigned-char -fno-common -Qunused-arguments -pthread -stdlib=libc++ -std=gnu++20 -arch arm64 -isysroot 
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.2.sdk -fPIC    -m64 -pipe -fsigned-char -fno-common -Qunused-arguments -pthread -stdlib=libc++ -MD -MT CMakeFiles/cx_tf_container.dir/TFAsroFile.cxx.o -MF CMakeFiles/cx_tf_container.dir/TFAsroFile.cxx.o.d -o CMakeFiles/cx_tf_container.dir/TFAsroFile.cxx.o -c /Users/chenxu/software/chenxufunc/git/tools/astroROOT/tf_container/TFAsroFile.cxx

In file included from /Users/chenxu/software/chenxufunc/git/tools/astroROOT/tf_container/TFAsroFile.cxx:30:
/Users/chenxu/software/ROOT/install/include/Bswapcpy.h:54:10: error: invalid output constraint '=&c' in asm
   54 |         :"=&c" (d0), "=&D" (d1), "=&S" (d2), "=&a" (d3)
      |          ^
/Users/chenxu/software/ROOT/install/include/Bswapcpy.h:76:10: error: invalid output constraint '=&c' in asm
   76 |         :"=&c" (d0), "=&D" (d1), "=&S" (d2), "=&a" (d3)

how to compile the byteswap with “=&c” on mac M1?

[cxwx1]

It seem the ROOT has change the way to swap bytes for arm machine

#if (defined(__linux) || defined(__APPLE__)) && defined(__i386__) && \
     defined(__GNUC__)
#define USE_BSWAPCPY
#endif

#ifdef USE_BSWAPCPY
#include "Bswapcpy.h"
#endif