[patch] [libcxx] cmakelists.txt patch to disable int to bool error warning for msvc

[Reid Kleckner]

Clang and gcc have a concept of "system" headers, for which they suppress
all warnings.  It's assumed that the user doesn't care about unactionable
warnings in code they don't own.

I believe MSVC doesn't make this distinction, so I worry that some user
might try to build with /W3, and warnings from libc++ headers.

Both of your previous fixes were in headers, in which case we may actually
want to commit them or use #pragma warning(push) #pragma warning(disable :
4800) ... #pragma warning pop().  Your original fix is probably less ugly
than the pragma.

Sorry for running you around!  :(  If the warning had been in source code,
this fix would work.  This is still probably worth committing, since we
don't care about these warnings at all in .cpp files.


On Wed, Oct 9, 2013 at 7:30 AM, G M <gmisocpp at gmail.com> wrote:

> Hi Everyone
>
> Here's a patch to disable implicit int to bool warnings for msvc libcxx by
> changing the project file default to silence this warning.
>
> There are about a dozen or so instances of this warning in libcxx and I am
> happy to make those changes manually if consensus forms to prefer that but
> so far that isn't the case.
>
> It's simply changing things like bool b = x & m; to b = (x&m) != 0;
>
> In absence of consensus to me making these types of changes I've gone with
> this change to the project file to disable the warnings instead. This
> change only effects MSVC, other compilers already default to this it seems.
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20131009/11e5892d/attachment.html>