[preamble] Also record the "skipping" state of the preprocessor

When a preamble ends in a conditional preprocessor block that is being
skipped, the preprocessor needs to continue skipping that block when
the preamble is used.

This fixes PR34570.

llvm-svn: 317308

1 files changed, 7 insertions, 0 deletions

diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp
index 65df6a57f1d..d80899de8f8 100644
--- a/clang/lib/Lex/Preprocessor.cpp
+++ b/clang/lib/Lex/Preprocessor.cpp
@@ -550,6 +550,13 @@ void Preprocessor::replayPreambleConditionalStack() {
            "CurPPLexer is null when calling replayPreambleConditionalStack.");
     CurPPLexer->setConditionalLevels(PreambleConditionalStack.getStack());
     PreambleConditionalStack.doneReplaying();
+    if (PreambleConditionalStack.reachedEOFWhileSkipping())
+      SkipExcludedConditionalBlock(
+          PreambleConditionalStack.SkipInfo->HashTokenLoc,
+          PreambleConditionalStack.SkipInfo->IfTokenLoc,
+          PreambleConditionalStack.SkipInfo->FoundNonSkipPortion,
+          PreambleConditionalStack.SkipInfo->FoundElse,
+          PreambleConditionalStack.SkipInfo->ElseLoc);
   }
 }