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>
diff --git a/third_party/llvm-10.0/configs/windows/include/llvm/Config/config.h b/third_party/llvm-10.0/configs/windows/include/llvm/Config/config.h
index 3dc0d0f..da3677c 100644
--- a/third_party/llvm-10.0/configs/windows/include/llvm/Config/config.h
+++ b/third_party/llvm-10.0/configs/windows/include/llvm/Config/config.h
@@ -347,7 +347,7 @@
#define RETSIGTYPE void
/* Define if std::is_trivially_copyable is supported */
-#define HAVE_STD_IS_TRIVIALLY_COPYABLE 1
+/* #undef HAVE_STD_IS_TRIVIALLY_COPYABLE */
/* Define to a function implementing stricmp */
#define stricmp _stricmp
