Fix for PR2747: allow pointer->int casts with a null base; these are

offset-of-like expressions.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@55627 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 0 deletions

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 7e60da5af3..564f530191 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -1163,6 +1163,13 @@ bool Sema::CheckArithmeticConstantExpression(const Expr* Init) {
     if (SubExpr->getType()->isArithmeticType())
       return CheckArithmeticConstantExpression(SubExpr);
 
+    if (SubExpr->getType()->isPointerType()) {
+      const Expr* Base = FindExpressionBaseAddress(SubExpr);
+      // If the pointer has a null base, this is an offsetof-like construct
+      if (!Base)
+        return CheckAddressConstantExpression(SubExpr);
+    }
+
     Diag(Init->getExprLoc(),
          diag::err_init_element_not_constant, Init->getSourceRange());
     return true;