[AST] Don't crash when comparing incomplete object
We cannot tell if an object is past-the-end if its type is incomplete.
Zero sized objects satisfy past-the-end criteria and our object might
turn out to be such an object.
This fixes PR24622.
llvm-svn: 246359
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 6350ff1..8aea10d 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -6602,9 +6602,15 @@
!LV.getLValueDesignator().isOnePastTheEnd())
return false;
+ // A pointer to an incomplete type might be past-the-end if the type's size is
+ // zero. We cannot tell because the type is incomplete.
+ QualType Ty = getType(LV.getLValueBase());
+ if (Ty->isIncompleteType())
+ return true;
+
// We're a past-the-end pointer if we point to the byte after the object,
// no matter what our type or path is.
- auto Size = Ctx.getTypeSizeInChars(getType(LV.getLValueBase()));
+ auto Size = Ctx.getTypeSizeInChars(Ty);
return LV.getLValueOffset() == Size;
}