[clang] [Clang] Fix Crash in Sema::DiagnoseUnguardedAvailability On 'if' With No Condition (PR #220004)

[via cfe-commits]

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@@ -1068,7 +1068,12 @@ ExtractedAvailabilityExpr extractAvailabilityExpr(const Expr *IfCond) {
 }
 
 bool DiagnoseUnguardedAvailability::TraverseIfStmt(IfStmt *If) {
-  ExtractedAvailabilityExpr IfCond = extractAvailabilityExpr(If->getCond());
+  Expr *Cond = If->getCond();
+  if (!Cond) {
+    return DynamicRecursiveASTVisitor::TraverseIfStmt(If);
+  }
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tadeuszjt wrote:

Fixed in latest push

https://github.com/llvm/llvm-project/pull/220004