commit feb03012c7bccf058491741febcaff3108ab4fa8
author Louis Dionne <ldionne.2@gmail.com> Mon Nov 28 08:39:42 2022 -0500
committer Copybara-Service <copybara-worker@google.com> Mon Nov 28 08:14:45 2022 -0800
tree f78b0187765883c24cf1003eafd47e4aa44fcf2b
parent a5a265240cfadc57b07590e1a9206466f1f513ba

[libc++][NFC] Add assertions before calling memmove

Since we're checking preconditions for calling memmove, we might
as well do that properly.

Differential Revision: https://reviews.llvm.org/D138798

NOKEYCHECK=True
GitOrigin-RevId: b95379d20e0493d4ca073fbaa2f878344568425b

include/fstream

diff --git a/include/fstream b/include/fstream
index 65b22a4..62c6f53 100644
--- a/include/fstream
+++ b/include/fstream
@@ -754,7 +754,8 @@
         else
         {
             if (__extbufend_ != __extbufnext_) {
-                _LIBCPP_ASSERT(__extbufnext_ != nullptr, "underflow moving from NULL" );
+                _LIBCPP_ASSERT(__extbufnext_ != nullptr, "underflow moving from nullptr");
+                _LIBCPP_ASSERT(__extbuf_ != nullptr, "underflow moving into nullptr");
                 _VSTD::memmove(__extbuf_, __extbufnext_, __extbufend_ - __extbufnext_);
             }
             __extbufnext_ = __extbuf_ + (__extbufend_ - __extbufnext_);