diff --git a/vm/math.cpp b/vm/math.cpp
index 37d3d0df7e..0e57c510a3 100644
--- a/vm/math.cpp
+++ b/vm/math.cpp
@@ -223,7 +223,7 @@ void factor_vm::primitive_format_float() {
   std::ostringstream localized_stream;
   try {
     localized_stream.imbue(std::locale(locale));
-  } catch (const runtime_error& error) {
+  } catch (const runtime_error&) {
     byte_array* array = allot_byte_array(1);
     array->data<char>()[0] = '\0';
     ctx->replace(tag<byte_array>(array));
@@ -248,7 +248,7 @@ void factor_vm::primitive_format_float() {
   localized_stream << value;
   const std::string& tmp = localized_stream.str();
   const char* cstr = tmp.c_str();
-  int size = tmp.length()+1;
+  size_t size = tmp.length()+1;
   byte_array* array = allot_byte_array(size);
   memcpy(array->data<char>(), cstr, size);
   ctx->replace(tag<byte_array>(array));