261598 2023-09-15 02:25:01 -0700 [MSVC][Win] Using C++20's concept cause WinCairo compiler to crash 2024-05-10 21:45:38 -0700 1 1 1 Unclassified WebKit Tools / Tests WebKit Nightly Build Unspecified Unspecified RESOLVED DUPLICATE 274018 P2 Normal --- 1 jean-yves.avenard webkit-unassigned fujii oldest_to_newest 1977653 0 jean-yves.avenard 2023-09-15 02:25:01 -0700 (Using Tools / Test component for lack of a better component) I added usage of C++20 concept in a PR, WinCairo bots crashes when parsing that file. https://ews-build.webkit.org/#/builders/32/builds/17174 This is the added code causing an issue: ``` class NativePromiseBase; template <typename T> concept IsNativePromise = std::is_base_of<NativePromiseBase, T>::value; template <typename T, typename U> concept RelatedNativePromise = requires(T, U) { { IsNativePromise<T> }; { IsNativePromise<U> }; { std::is_same<typename T::NativePromiseBaseType, typename U::NativePromiseBaseType>::value }; }; ``` 1977654 1 jean-yves.avenard 2023-09-15 02:25:30 -0700 The compiler crashes with: ``` C:\BW\WinCairo-EWS\build\WebKitBuild\Release\WTF\Headers\wtf/TypeTraits.h(134): fatal error C1001: Internal compiler error. ``` 1977658 2 jean-yves.avenard 2023-09-15 03:21:11 -0700 I can confirm that it's just this one: ``` template <typename T, typename U> concept RelatedNativePromise = requires(T, U) { { IsNativePromise<T> }; { IsNativePromise<U> }; { std::is_same<typename T::NativePromiseBaseType, typename U::NativePromiseBaseType>::value }; }; ``` that causes the crash 1983021 3 jean-yves.avenard 2023-10-05 16:32:14 -0700 Wth the migration from mcvc to clang-cl this may no longer be an issue. 1983054 4 fujii 2023-10-05 17:38:05 -0700 The migration isn't completed yet. I will remove the #if after the migration is completed. 2030143 5 fujii 2024-04-22 01:09:15 -0700 WebKit Windows port hasn't dropped MSVC support yet. VS 2022 v17.9.6 still reports the internal compiler error for wtf/TypeTraits.h. 2034684 6 fujii 2024-05-10 21:45:38 -0700 *** This bug has been marked as a duplicate of bug 274018 ***