[Bug libstdc++/99306] cross compiler bootstrap failure on msdosdjgpp: error: alignment of 'm' is greater than maximum object file alignment 16

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99306

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-03-01
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
  __gnu_cxx::__mutex&
  get_mutex(unsigned char i)
  {
    // increase alignment to put each lock on a separate cache line
    struct alignas(64) M : __gnu_cxx::__mutex { };
    static M m[mask + 1];
    return m[i];

there's __BIGGEST_ALIGNMENT__ one could use as bound but that will usually
be lower than the max ofile alignment and on most targets likely less
than 64.  That value (64) looks like it should be target dependent anyway
(configury?)