[clang] [clang-cl] Fix value of __FUNCTION__ in MSVC mode. (PR #84014)

[Zahira Ammarguellat via cfe-commits]

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@@ -1635,6 +1635,17 @@ void TypePrinter::printElaboratedBefore(const ElaboratedType *T,
     if (T->getKeyword() != ElaboratedTypeKeyword::None)
       OS << " ";
     NestedNameSpecifier *Qualifier = T->getQualifier();
+    if (!Policy.SuppressTagKeyword && Policy.SuppressScope &&
+        !Policy.SuppressUnwrittenScope) {
+      StringRef prefix = T->isClassType()       ? "class "
+                         : T->isStructureType() ? "struct "
+                         : T->isUnionType()     ? "union "
+                                                : "";
+      OS << prefix;
+      Policy.SuppressTagKeyword = true;
+      Policy.SuppressScope = false;
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zahiraam wrote:

Hmmm! Can't seem to find a test case that fails. At each step of  the printing  `ElaboratedTypePolicyRAII PolicyRAII(Policy);` gets called and that re-initializes the values of` Policy.SuppressTagKeyword` and  `Policy.SuppressScope` to true!

https://github.com/llvm/llvm-project/pull/84014