I've searched to see if that has already been reported. I apologize if this is a dupe.
In setting up my own preferences, I've modified my Base settings to expand tabs to spaces, but clearly in Makefiles, this has to be reversed. According to this page, sublimetext.com/docs/2/indentation.html, there are two User places for putting User settings. But at least in build 2059, they file-type specific version does not work.
From that page:
but when I place the following in Packages/User/Makefile.sublime-settings, the settings are never used:
// The number of spaces a tab is considered equal to
// Set to true to insert spaces when tab is pressed
Maybe I'm doing something fundamentally wrong.