[Sema] print more readable identifier of anonymous struct of -Wconsumed

[inclyc]

Summary

Working in D133574 we discovered -Wconsumed print '' with anonymous
class/struct. After this patch we give a line number, file name of
anonymous struct/class declaration.

Example:

struct S {
  struct {
    __attribute__((callable_when(consumed))) void func();
  } s;
};

local/anoy-consume.cpp:3:20: warning: consumed analysis attribute is attached to member of class 'S::(unnamed struct at local/anoy-consume.cpp:2:3)' which isn't marked as consumable [-Wconsumed]
    __attribute__((callable_when(consumed))) void func();
                   ^
1 warning generated.

Link: https://reviews.llvm.org/D133574#3817743
Link: https://godbolt.org/z/16vP3voTW

[aaron.ballman]

FWIW, I approached this in a slightly different way here: https://reviews.llvm.org/D134813 -- I've not landed it yet because I'm still hoping I can find a way to not modify lit just to fix one fragile test, but I think we ultimately want to go this other route because that fixes all of the places we pass in a TagDecl instead of playing whack-a-mole as we find new bad diagnostic behavior.

clang/docs/ReleaseNotes.rst

 - Correctly diagnose use of an integer literal without a suffix whose
   underlying type is ``long long`` or ``unsigned long long`` as an extension in
   C89 mode . Clang previously only diagnosed if the literal had an explicit
   ``LL`` suffix.
 - Clang now correctly diagnoses index that refers past the last possible element
   of FAM-like arrays.
 - Clang now correctly diagnoses a warning when defercencing a void pointer in C mode.
   This fixes `Issue 53631 <https://github.com/llvm/llvm-project/issues/53631>`_
+- Clang now prints more readable identifier for anonymous class/struct of
+  ``-Wconsumed``.
 
 Non-comprehensive list of changes in this release
 -------------------------------------------------
 - It's now possible to set the crash diagnostics directory through
   the environment variable ``CLANG_CRASH_DIAGNOSTICS_DIR``.
   The ``-fcrash-diagnostics-dir`` flag takes precedence.
 - When using header modules, inclusion of a private header and violations of
   the `use-declaration rules

clang/lib/Sema/SemaDeclAttr.cpp

 }
 
 static bool checkForConsumableClass(Sema &S, const CXXMethodDecl *MD,
                                     const ParsedAttr &AL) {
   QualType ThisType = MD->getThisType()->getPointeeType();
 
   if (const CXXRecordDecl *RD = ThisType->getAsCXXRecordDecl()) {
     if (!RD->hasAttr<ConsumableAttr>()) {
-      S.Diag(AL.getLoc(), diag::warn_attr_on_unconsumable_class) << RD;
+      S.Diag(AL.getLoc(), diag::warn_attr_on_unconsumable_class)
+          << S.Context.getTagDeclType(RD);
 
       return false;
     }
   }
 
   return true;
 }
 

clang/test/SemaCXX/warn-consumed-parsing.cpp

 
 
 class CONSUMABLE(unconsumed)
       __attribute__((consumable_auto_cast_state))
       __attribute__((consumable_set_state_on_read))
       Status {
 };
 
-
-
+class Anonymous {
+  struct /* anonymous */ {
+    void callableWhen()   CALLABLE_WHEN("unconsumed"); // expected-warning-re {{consumed analysis attribute is attached to member of class 'Anonymous::(unnamed struct at {{.*}})' which isn't marked as consumable}}
+    void consumes()       SET_TYPESTATE(consumed); // expected-warning-re {{consumed analysis attribute is attached to member of class 'Anonymous::(unnamed struct at {{.*}})' which isn't marked as consumable}}
+    bool testUnconsumed() TEST_TYPESTATE(consumed); // expected-warning-re {{consumed analysis attribute is attached to member of class 'Anonymous::(unnamed struct at {{.*}})' which isn't marked as consumable}}
+  } anonymous;
+};