[clang] [Clang] diagnosing missing Vulkan environment when using SPIR-V triple (PR #190840)

[Fangrui Song via cfe-commits]

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@@ -43,6 +43,9 @@ def note_fe_backend_resource_limit: Note<"%0 (%1) exceeds limit (%2) in '%3'">,
 def remark_fe_backend_plugin: Remark<"%0">, BackendInfo, InGroup<RemarkBackendPlugin>;
 def note_fe_backend_plugin: Note<"%0">, BackendInfo;
 
+def err_fe_spirv_requires_vulkan : Error<
+    "SPIR-V target requires a Vulkan environment (e.g. '-target spirv64-unknown-vulkan1.3')">;
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MaskRay wrote:

It's very unusual to suggest a `e.g.` (In addition, the version information can become stale quickly)

https://github.com/llvm/llvm-project/pull/190840