diff --git a/indra/newview/llmeshrepository.cpp b/indra/newview/llmeshrepository.cpp
index b8cbd414ae..970dd60539 100644
--- a/indra/newview/llmeshrepository.cpp
+++ b/indra/newview/llmeshrepository.cpp
@@ -1971,9 +1971,11 @@ EMeshProcessingResult LLMeshRepoThread::headerReceived(const LLVolumeParams& mes
 	if (data_size > 0)
 	{
 		llssize dsize = data_size;
-		char* result_ptr = strip_deprecated_header((char*)data, dsize, &header_size);
+		llssize header_size_tmp{};
+		char* result_ptr = strip_deprecated_header((char*)data, dsize, &header_size_tmp);
+		header_size = static_cast<U32>(header_size_tmp);
 
-		data_size = dsize;
+		data_size = static_cast<S32>(dsize);
 
 		boost::iostreams::stream<boost::iostreams::array_source> stream(result_ptr, data_size);