\gromacs{} can be compiled for any distribution of Linux, Mac OS X,
Windows (native, Cygwin or MinGW), BlueGene, Cray and many other
architectures. Technically, it can be compiled on any platform with
-an ANSI C89 compiler, an ISO C++98 compiler, and supporting libraries,
+an ANSI C99 compiler, an ISO C++98 compiler, and supporting libraries,
such as the GNU C library. However, \gromacs{} also comes with many
hardware-specific extensions to provide very high performance on those
platforms, and to enable these we have slightly more specific
requirements since old compilers do not support new features, or they
-can be buggy.
+can be buggy. Not all of the C99 standard is required and some C89
+compilers (including Microsoft Visual C) will also be able to compile
+Gromacs.
\subsection{Compiler}