Merge remote-tracking branch 'origin/main' into rebranch

Author: swift-ci

include/swift/Runtime/Config.h

@@ -168,6 +168,14 @@ extern uintptr_t __COMPATIBILITY_LIBRARIES_CANNOT_CHECK_THE_IS_SWIFT_BIT_DIRECTL
 // Bring in visibility attribute macros
 #include "swift/shims/Visibility.h"
 
+// Temporary definitions to allow compilation on clang-15.
+#if defined(__cplusplus)
+#define SWIFT_EXTERN_C extern "C"
+#else
+#define SWIFT_EXTERN_C
+#endif
+#define SWIFT_RUNTIME_EXPORT_ATTRIBUTE SWIFT_EXPORT_FROM_ATTRIBUTE(swiftCore)
+
 // Define mappings for calling conventions.
 
 // Annotation for specifying a calling convention of