STINNER Victor <vstin...@python.org> added the comment:
> The current implementation tests the ``__GNUC__`` and ``__GNUC_MINOR__`` > macros as the logic (GCC version >= 4.5) for determining whether the compiler > intrinsic ``__builtin_unreachable()`` is present (see commits eebaa9bf, > 24ba3b0d). However, Clang defines these macros too and can cause confusion. > Clang 11 pretends to be GCC 4.2.1 in its predefined macros. As a result, > Clang won't use the intrinsic even if it's supported. This doesn't seem to > match the intent behind the original implementation. Hum. The current code is: #elif defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)) # define Py_UNREACHABLE() __builtin_unreachable() #elif defined(__clang__) || defined(__INTEL_COMPILER) # define Py_UNREACHABLE() __builtin_unreachable() Even if clang pretends to be GCC 4.2 and the first test fails, the second test is true and so Py_UNREACHABLE() is always defined as __builtin_unreachable() on clang, no? You can please better explain your problem? You can write a short C code demonstrating the bug? ---------- nosy: +vstinner _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue43615> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
