commit 4d1eb2d5cb97b99fc0d8559661a7b569dc8ecc90
author Erik Verbruggen <erikjv@me.com> Fri Nov 03 09:40:07 2017 +0000
committer Erik Verbruggen <erikjv@me.com> Fri Nov 03 09:40:07 2017 +0000
tree 41228f5cc84ebac7b103b02ef68f181967647fae
parent 8c825db25e32365652c9d68177224f8c3c1a551a

[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

clang/lib/Lex/PPDirectives.cpp

diff --git a/clang/lib/Lex/PPDirectives.cpp b/clang/lib/Lex/PPDirectives.cpp
index f9a9750..ca3e70f 100644
--- a/clang/lib/Lex/PPDirectives.cpp
+++ b/clang/lib/Lex/PPDirectives.cpp
@@ -350,7 +350,7 @@
 /// If ElseOk is true, then \#else directives are ok, if not, then we have
 /// already seen one so a \#else directive is a duplicate.  When this returns,
 /// the caller can lex the first valid token.
-void Preprocessor::SkipExcludedConditionalBlock(const Token &HashToken,
+void Preprocessor::SkipExcludedConditionalBlock(SourceLocation HashTokenLoc,
                                                 SourceLocation IfTokenLoc,
                                                 bool FoundNonSkipPortion,
                                                 bool FoundElse,
@@ -358,8 +358,11 @@
   ++NumSkipped;
   assert(!CurTokenLexer && CurPPLexer && "Lexing a macro, not a file?");
 
-  CurPPLexer->pushConditionalLevel(IfTokenLoc, /*isSkipping*/false,
-                                 FoundNonSkipPortion, FoundElse);
+  if (PreambleConditionalStack.reachedEOFWhileSkipping())
+    PreambleConditionalStack.clearSkipInfo();
+  else
+    CurPPLexer->pushConditionalLevel(IfTokenLoc, /*isSkipping*/ false,
+                                     FoundNonSkipPortion, FoundElse);
 
   if (CurPTHLexer) {
     PTHSkipExcludedConditionalBlock();
@@ -385,6 +388,9 @@
       // We don't emit errors for unterminated conditionals here,
       // Lexer::LexEndOfFile can do that propertly.
       // Just return and let the caller lex after this #include.
+      if (PreambleConditionalStack.isRecording())
+        PreambleConditionalStack.SkipInfo.emplace(
+            HashTokenLoc, IfTokenLoc, FoundNonSkipPortion, FoundElse, ElseLoc);
       break;
     }
 
@@ -554,7 +560,7 @@
 
   if (Callbacks)
     Callbacks->SourceRangeSkipped(
-        SourceRange(HashToken.getLocation(), CurPPLexer->getSourceLocation()),
+        SourceRange(HashTokenLoc, CurPPLexer->getSourceLocation()),
         Tok.getLocation());
 }
 
@@ -2676,7 +2682,8 @@
   if (MacroNameTok.is(tok::eod)) {
     // Skip code until we get to #endif.  This helps with recovery by not
     // emitting an error when the #endif is reached.
-    SkipExcludedConditionalBlock(HashToken, DirectiveTok.getLocation(),
+    SkipExcludedConditionalBlock(HashToken.getLocation(),
+                                 DirectiveTok.getLocation(),
                                  /*Foundnonskip*/ false, /*FoundElse*/ false);
     return;
   }
@@ -2725,7 +2732,8 @@
                                      /*foundelse*/false);
   } else {
     // No, skip the contents of this block.
-    SkipExcludedConditionalBlock(HashToken, DirectiveTok.getLocation(),
+    SkipExcludedConditionalBlock(HashToken.getLocation(),
+                                 DirectiveTok.getLocation(),
                                  /*Foundnonskip*/ false,
                                  /*FoundElse*/ false);
   }
@@ -2772,7 +2780,7 @@
                                    /*foundnonskip*/true, /*foundelse*/false);
   } else {
     // No, skip the contents of this block.
-    SkipExcludedConditionalBlock(HashToken, IfToken.getLocation(),
+    SkipExcludedConditionalBlock(HashToken.getLocation(), IfToken.getLocation(),
                                  /*Foundnonskip*/ false,
                                  /*FoundElse*/ false);
   }
@@ -2837,7 +2845,8 @@
   }
 
   // Finally, skip the rest of the contents of this block.
-  SkipExcludedConditionalBlock(HashToken, CI.IfLoc, /*Foundnonskip*/ true,
+  SkipExcludedConditionalBlock(HashToken.getLocation(), CI.IfLoc,
+                               /*Foundnonskip*/ true,
                                /*FoundElse*/ true, Result.getLocation());
 }
 
@@ -2881,7 +2890,7 @@
   }
 
   // Finally, skip the rest of the contents of this block.
-  SkipExcludedConditionalBlock(HashToken, CI.IfLoc, /*Foundnonskip*/ true,
-                               /*FoundElse*/ CI.FoundElse,
-                               ElifToken.getLocation());
+  SkipExcludedConditionalBlock(
+      HashToken.getLocation(), CI.IfLoc, /*Foundnonskip*/ true,
+      /*FoundElse*/ CI.FoundElse, ElifToken.getLocation());
 }

clang/lib/Lex/Preprocessor.cpp

diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp
index 65df6a5..d80899d 100644
--- a/clang/lib/Lex/Preprocessor.cpp
+++ b/clang/lib/Lex/Preprocessor.cpp
@@ -550,6 +550,13 @@
            "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);
   }
 }