to reflect the new license. These used slightly different spellings that
defeated my regular expressions.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351648
These calls are allowed to fail spuriously.
29.6.5.25:
Remark: A weak compare-and-exchange operation may fail spuriously.
That is, even when the contents of memory referred to by expected
and object are equal, it may return false and store back to expected
the same memory contents that were originally there. [ Note: This
spurious failure enables implementation of compare and-exchange on a
broader class of machines, e.g., load-locked store-conditional
machines. A consequence of spurious failure is that nearly all uses
of weak compare-and-exchange will be in a loop.
To fix this, we replace any assert() that expects
std::atomic::compare_exchange_weak() to return true with a loop. If the
call does not return true within N runs (with N currently equal to 10),
then the test fails.
http://llvm.org/bugs/show_bug.cgi?id=20546
llvm-svn: 217319
Olivier Giroux