clion-custom-defined-compiler-examples

16-bit Windows: don't know how to make it work, patches welcome
Windows for MIPS, PowerPC or Alpha: the compilers are there, but the libraries are not made, contribute to Open Watcom 2 to make it possible
QNX: headers and libraries are copyright of BlackBerry Limited, ping them for opensourcing them (as they were for QNX 2 and QNX 4 probably not of much interest to them anymore?)
NetWare: libraries are there but headers need to be installed separately, ping Micro Focus International for opensourcing them (as they abandoned NetWare long ago)
Others: Watcom supported many targets over the ages and I don't know which others may just need some care to make them work

Instructions

The most important step is to ensure that Watcom binaries are in the path. This depends on your exact installation but usually on Windows it is C:\WATCOM\BINNT64 and on Linux it is /opt/watcom/binl64. Until JetBrains allow to specify APPENDING path members for a specific toolchain (tried with Environment Variables, no go) this is a must.

After this is done you need to add the compilers in Settings -> Build, Execution, Deployment -> Toolchains and set up at least the C compiler and C++ compiler (they're the same) and at least in Windows (as there's no system make to make CLion happy) also select wmake (wmake.exe).

Compiler for 16-bit targets: wcl or wcl.exe Compiler for 32-bit targets: wcl386 or wcl386.exe Compiler for Alpha targets: wclaxp or wclaxp.exe DOESN'T INCLUDE C OR C++ LIBRARIES Compiler for MIPS targets: wclmps or wclmps.exe DOESN'T INCLUDE C OR C++ LIBRARIES Compiler for PowerPC targets: wclppc or wclppc.exe DOESN'T INCLUDE C OR C++ LIBRARIES

Then, for the project, you need to go Settings -> Build, Execution, Deployment -> CMake and create the appropriate targets.

In each target set the following environment for Windows (change paths appropriately if installed in another location):

WATCOM=C:\WATCOM
INCLUDE=C:\WATCOM\H\;C:\WATCOM\H\NT\;C:\WATCOM\H\NT\DIRECTX\;C:\WATCOM\H\NT\DDK\;%INCLUDE%

or in Linux (change paths appropriately if installed in another location):

WATCOM=/opt/watcom
INCLUDE=/opt/watcom/lh

then in CMake options you need to set: -DCMAKE_SYSTEM_NAME=<system> -DCMAKE_SYSTEM_PROCESSOR=<arch> -G "Watcom WMake"

where <system> is:

DOS for DOS
OS2 for OS/2
Windows for Windows and Windows NT
Linux for Linux

and <arch> is:

I86 for 16-bit
I386 for 32-bit
none for 32-bit or the others (untested)

Final notes

The preprocessor macros have been a bestguess and may be severely incomplete, patches welcome!

2021 - Natalia Portillo Many thanks to Jiří Malák for keeping OpenWatcom alive!