diff --git a/source/Commands/CommandObjectExpression.cpp b/source/Commands/CommandObjectExpression.cpp
index abaf4c6..703e135 100644
--- a/source/Commands/CommandObjectExpression.cpp
+++ b/source/Commands/CommandObjectExpression.cpp
@@ -424,7 +424,7 @@
                     const char *error_cstr = result_valobj_sp->GetError().AsCString();
                     if (error_cstr && error_cstr[0])
                     {
-                        int error_cstr_len = strlen (error_cstr);
+                        const size_t error_cstr_len = strlen (error_cstr);
                         const bool ends_with_newline = error_cstr[error_cstr_len - 1] == '\n';
                         if (strstr(error_cstr, "error:") != error_cstr)
                             error_stream->PutCString ("error: ");