Make the -Wreinterpret-base-class logic safe against invalid

declarations at any point. Patch by Alexander Zinenko, and
report by Richard Smith.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178098 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 15 insertions, 6 deletions

diff --git a/lib/Sema/SemaCast.cpp b/lib/Sema/SemaCast.cpp
index 1dbc9aaca5..0e19adfd28 100644
--- a/lib/Sema/SemaCast.cpp
+++ b/lib/Sema/SemaCast.cpp
@@ -695,14 +695,15 @@ static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr,
   const CXXRecordDecl *SrcRD =
     SrcPointeeRD ? SrcPointeeRD : SrcType->getAsCXXRecordDecl();
 
-  // Examining subobjects for records is only possible if the complete
-  // definition is available.  Also, template instantiation is not allowed here.
-  if(!SrcRD || !SrcRD->isCompleteDefinition())
+  // Examining subobjects for records is only possible if the complete and
+  // valid definition is available.  Also, template instantiation is not
+  // allowed here.
+  if (!SrcRD || !SrcRD->isCompleteDefinition() || SrcRD->isInvalidDecl())
     return;
 
   const CXXRecordDecl *DestRD = DestType->getPointeeCXXRecordDecl();
 
-  if(!DestRD || !DestRD->isCompleteDefinition())
+  if (!DestRD || !DestRD->isCompleteDefinition() || DestRD->isInvalidDecl())
     return;
 
   enum {
@@ -721,7 +722,7 @@ static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr,
 
   bool VirtualBase = true;
   bool NonZeroOffset = false;
-  for (CXXBasePaths::const_paths_iterator I = BasePaths.begin(), 
+  for (CXXBasePaths::const_paths_iterator I = BasePaths.begin(),
                                           E = BasePaths.end();
        I != E; ++I) {
     const CXXBasePath &Path = *I;
@@ -734,8 +735,16 @@ static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr,
         break;
       const CXXRecordDecl *BaseRD = IElem->Base->getType()->getAsCXXRecordDecl();
       assert(BaseRD && "Base type should be a valid unqualified class type");
+      // Don't check if any base has invalid declaration or has no definition
+      // since it has no layout info.
+      const CXXRecordDecl *Class = IElem->Class,
+                          *ClassDefinition = Class->getDefinition();
+      if (Class->isInvalidDecl() || !ClassDefinition ||
+          !ClassDefinition->isCompleteDefinition())
+        return;
+
       const ASTRecordLayout &DerivedLayout =
-          Self.Context.getASTRecordLayout(IElem->Class);
+          Self.Context.getASTRecordLayout(Class);
       Offset += DerivedLayout.getBaseClassOffset(BaseRD);
     }
     if (!IsVirtual) {