List of C compiler for Windows

[cnoob]

Visual Studio build tool
MinGW (I currently use: http://www.equation.com/servlet/equation.cmd?fa=fortran)
Clang (I currently use: https://github.com/mstorsjo/llvm-mingw)
TCC (https://savannah.nongnu.org/projects/tinycc)
PCC (http://pcc.ludd.ltu.se/ftp/pub/win32/)
OCC (http://www.members.tripod.com/~ladsoft/orange_c_compiler.html)
POCC 

[Abraham]

TCC and PCC are limited to C99.

Not sure about Visual C++ and it's weird reverse compatibility.
C11 took atomic and thread from C++11, so it has those as well.
C++11 requires most of C99, except for a few things like VLA.
C++14 requires many things from C11, but not everything.
There is not need to support _Generic because templates are better in C++.

MinGW and Clang are up to standards.

POCC is clearly the one in the lead to matching standards.

[cosh]

And...
Open Watcom C (http://www.openwatcom.org/)

[TimoVJL]

And...
Open Watcom C (http://www.openwatcom.org/)

Open Watcom v2 Fork