tree ed8a80a22b28a7b517019b760a32798254387535
parent d9a9ccd8cb5f195ae6cda516529667962ec743fb
author Liu Hao <lh_mouse@126.com> 1597672001 +0800
committer Liu Hao <lh_mouse@126.com> 1597672001 +0800

winpthreads: Call `_fpreset()` for new threads

This is necessary for math functions taking `long double` arguments to
work reliably, as by default, new threads have their x87 precision set
to 53 bits.

Note the x87 control word can't be set in the TLS callback. It gets
overwritten before the thread procedure begins execution. There is NO
workaround for the win32 thread model, other than requiring users to
call `_fpreset()` themselves.

Reference: https://sourceforge.net/p/mingw-w64/mailman/message/37084134/
Signed-off-by: Liu Hao <lh_mouse@126.com>