[clang] [Clang] Treat the body of an expansion statement with expansion size 0 as discarded (PR #212319)

[Oliver Hunt via cfe-commits]

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@@ -3666,7 +3668,8 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       S = CXXExpansionStmtPattern::CreateEmpty(
           Context, Empty,
           static_cast<CXXExpansionStmtPattern::ExpansionStmtKind>(
-              Record[ASTStmtReader::NumStmtFields]));
+              Record[ASTStmtReader::NumStmtFields]),
+          Record[ASTStmtReader::NumStmtFields + 1]);
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ojhunt wrote:

diff is difficult to read here: is this indented correctly?

https://github.com/llvm/llvm-project/pull/212319