Re: [libvirt] [PATCH] util: Fix build with clang

When compiling with clang on Linux, it complains that "passing an object that undergoes default argument promotion to 'va_start' has undefined behavior". That is true according to the C standard, although I couldn't find any mention about enum->int promotion (even though it's a sensible one). The only fix I came up with was changing the layer parameter to int so that it does not undergo any default argument promotion.