[clang] [LifetimeSafety] Add fix-it for misplaced lifetimebound attributes (PR #199149)

[David Meng via cfe-commits]

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@@ -27,11 +27,10 @@ struct S {
   );
   
   const MyObj &both(const MyObj &  // expected-warning {{'lifetimebound' attribute on this definition is not visible to callers before the definition; add it to the declaration instead}}
-      // CHECK: fix-it:"{{.*}}":{[[@LINE+4]]:{{[0-9]+}}-[[@LINE+4]]:{{[0-9]+}}}:" {{\[\[clang::lifetimebound\]\]}}"
-      obj,
-      // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:{{[0-9]+}}-[[@LINE-1]]:{{[0-9]+}}}:" {{\[\[clang::lifetimebound\]\]}}"
+      obj,  // CHECK-DAG: fix-it:"{{.*}}":{[[@LINE]]:{{[0-9]+}}-[[@LINE]]:{{[0-9]+}}}:" {{\[\[clang::lifetimebound\]\]}}"
       bool
   );  // expected-warning {{'lifetimebound' attribute on this definition is not visible to callers before the definition; add it to the declaration instead}}
+      // CHECK-DAG: fix-it:"{{.*}}":{[[@LINE-1]]:{{[0-9]+}}-[[@LINE-1]]:{{[0-9]+}}}:" {{\[\[clang::lifetimebound\]\]}}"
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davidmenggx wrote:

I don't believe this works because `@LINE` works on the absolute line number so the continuation `\` doesn't apply

At least this is what I see when testing locally

Source ? https://llvm.org/docs/CommandGuide/FileCheck.html#filecheck-pseudo-numeric-variables

https://github.com/llvm/llvm-project/pull/199149