[clang] [clang][Modules] Complete the implementation of P2615: Meaningful exports (PR #194201)

[Yihan Wang via cfe-commits]

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@@ -3,9 +3,135 @@
 
 
 // RUN: %clang_cc1 -std=c++20 -verify -fsyntax-only %t/A.cpp
+// RUN: %clang_cc1 -std=c++20 -verify -fsyntax-only %t/B.cpp
+// RUN: not %clang_cc1 -std=c++20 -fsyntax-only -fdiagnostics-parseable-fixits %t/B.cpp 2>&1 | FileCheck %t/B.cpp
+// RUN: %clang_cc1 -std=c++20 -verify -fsyntax-only %t/msvc-stl-exception-1.cpp
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yronglin wrote:

AFAIK, microsoft/STL uses many extensions specific to MSVC, such as __declspec, dllimport/dllexport, novtable (e.g., <future>, <functional>, <memory>, <system_error>), empty_bases (<generator>), appdomain (yvals.h), and intrinsics like _BitScan* and _Interlocked*. Therefore, users must enable the -fms-compatibility and -fms-extension options to compile Microsoft/STL.

https://github.com/llvm/llvm-project/pull/194201