tree 407ff2afe5d9670a6cf86311ab467bd554bea62c
parent ec3650f56ca2cc032a46ee4eeb86cccd2b78a6b5
author Nicolas Capens <capn@google.com> 1598385517 -0400
committer Nicolas Capens <nicolascapens@google.com> 1598624298 +0000

Work around std::is_trivially_copyable issue with MSVC

Microsoft Visual Studio Community 2019 Version 16.7.1 produced the
following errors:

C2976 'llvm::SmallVectorTemplateBase': too few template argument
SwiftShader\third_party\llvm-10.0\llvm\include\llvm\ADT\SmallVector.h:315

C2338 inconsistent behavior between llvm:: and std:: implementation of is_trivially_copyable
SwiftShader\third_party\llvm-10.0\llvm\include\llvm\Support\type_traits.h:181

Not defining LLVM's HAVE_STD_IS_TRIVIALLY_COPYABLE config makes it fall
back to code which doesn't use std::is_trivially_copyable and avoids the
issue.

Note this may hide a potentially serious MSVC compiler bug since C2338
is produced by a static_assert. Without that static assert we may not
have known about the unexpected std::is_trivially_copyable behavior
until run-time issues are caused by it.

Bug: swiftshader:153
Change-Id: I04ab6d8ae725ecab45ac27fd89a37213baa86943
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/47930
Presubmit-Ready: Nicolas Capens <nicolascapens@google.com>
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>