There is the possibility to check the configuration file
fullfile(prefdir,'compopts.bat')
on the 2nd line to contain the configured compiler or if the file exists at all.
Expected compilers and their names are:
lcc - for the LCC compiler msvc60 - for Microsoft Visual C++ 6.0 Professional msvc80 - for Microsoft Visual C++ 2005 Professional msvc90 - for Microsoft Visual C++ 2008 Professional msvc100 - for Microsoft Visual C++ 2010 Professional mssdk71 - for Microsoft Windows SDK 7.1