diff --git a/core/fxcrt/cfx_blockbuffer.cpp b/core/fxcrt/cfx_blockbuffer.cpp
index 7609fb9..aeef565 100644
--- a/core/fxcrt/cfx_blockbuffer.cpp
+++ b/core/fxcrt/cfx_blockbuffer.cpp
@@ -11,7 +11,7 @@
 
 namespace {
 
-const int kAllocStep = 1024 * 1024;
+const size_t kAllocStep = 1024 * 1024;
 
 }  // namespace
 
@@ -77,8 +77,7 @@
   size_t maybeDataLength = m_BufferSize - 1 - m_StartPosition;
   if (start > maybeDataLength)
     return CFX_WideString();
-  if (length > maybeDataLength)
-    length = maybeDataLength;
+  length = std::min(length, maybeDataLength);
 
   CFX_WideString wsTextData;
   wchar_t* pBuf = wsTextData.GetBuffer(length);
diff --git a/xfa/fde/xml/cfde_xmlsyntaxparser.cpp b/xfa/fde/xml/cfde_xmlsyntaxparser.cpp
index 9adf11b..57501cc 100644
--- a/xfa/fde/xml/cfde_xmlsyntaxparser.cpp
+++ b/xfa/fde/xml/cfde_xmlsyntaxparser.cpp
@@ -683,7 +683,7 @@
         }
       }
     }
-    if (m_iEntityStart > 0 &&
+    if (m_iEntityStart >= 0 &&
         m_BlockBuffer.GetDataLength() > static_cast<size_t>(m_iEntityStart)) {
       m_BlockBuffer.DeleteTextChars(m_BlockBuffer.GetDataLength() -
                                     m_iEntityStart);