[clang] Fix some static initialization race-conditions (PR #181367)

[Yanzuo Liu via cfe-commits]

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@@ -57,26 +58,24 @@ using namespace clang;
 #define ABSTRACT_STMT(STMT)
 #include "clang/AST/StmtNodes.inc"
 
-static struct StmtClassNameTable {
+struct StmtClassNameTable {
   const char *Name;
   unsigned Counter;
   unsigned Size;
-} StmtClassInfo[Stmt::lastStmtConstant+1];
+};
 
 static StmtClassNameTable &getStmtInfoTableEntry(Stmt::StmtClass E) {
-  static bool Initialized = false;
-  if (Initialized)
-    return StmtClassInfo[E];
-
-  // Initialize the table on the first use.
-  Initialized = true;
+  static std::array<StmtClassNameTable, Stmt::lastStmtConstant + 1>
+      stmtClassInfo = []() {
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zwuis wrote:

It's up to you, but parentheses could be omitted.

https://github.com/llvm/llvm-project/pull/181367