Fix crash when an 'import a module' TypoCorrection has its CorrectionDecls

replaced by visible decls.

Make sure that all paths through checkCorrectionVisibility set the
RequiresImport flag appropriately, so we don't end up using a stale value.
Patch by Jorge Gorbe!

Differential Revision: https://reviews.llvm.org/D30963

llvm-svn: 304745

1 files changed, 6 insertions, 7 deletions

diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index 1d32e579681..1fb25f4e0e7 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -3747,20 +3747,19 @@ static void LookupPotentialTypoResult(Sema &SemaRef,
                                       bool FindHidden);
 
 /// \brief Check whether the declarations found for a typo correction are
-/// visible, and if none of them are, convert the correction to an 'import
-/// a module' correction.
+/// visible. Set the correction's RequiresImport flag to true if none of the
+/// declarations are visible, false otherwise.
 static void checkCorrectionVisibility(Sema &SemaRef, TypoCorrection &TC) {
-  if (TC.begin() == TC.end())
-    return;
-
   TypoCorrection::decl_iterator DI = TC.begin(), DE = TC.end();
 
   for (/**/; DI != DE; ++DI)
     if (!LookupResult::isVisible(SemaRef, *DI))
       break;
-  // Nothing to do if all decls are visible.
-  if (DI == DE)
+  // No filtering needed if all decls are visible.
+  if (DI == DE) {
+    TC.setRequiresImport(false);
     return;
+  }
 
   llvm::SmallVector<NamedDecl*, 4> NewDecls(TC.begin(), DI);
   bool AnyVisibleDecls = !NewDecls.empty();