Advantages and disadvantages of Open Watcom [closed]

Question

Since in some post on StackOverflow it was recommended to try to support multiple (in this case C/C++) compilers if feasible, since this forces you to code more standard compliant and helps finding bugs.

So I was looking for additional free C/C++ compilers I could add support for to my project (it is written C/C++ (both languages combined)). I found Open Watcom to be an interesting candidate.

So my question is: what are the advantages and disadvantages of Open Watcom C/C++ compiler in comparison to other ones (for example gcc/g++, Visual C++ etc.)?

Answer 1

There are probably no particular advantages since if portable code is your aim you would generally try to restrict your code to the standard subset implemented by all compilers. I would say lowest common denominator but that may seem somewhat derogatory.

The advantages of one compiler over another generally lie in either the extensions it provides, the libraries it includes, or the performance of the generated code, if portability is your aim, you are probably interested in neither. It is not the advantages of one compiler over another that should interest you in this case, but rather its adherence to and compliance with the ISO standards.

In its earlier commercial incarnation, Watcom was famously one of the best optimising compilers available; I doubt however whether it has kept pace with processor development since then however (or even the transition for 16 bit to 32 bit x86!).

Its one feature that may be seen as an advantage in some cases is that it supports DOS, OS/2 and Windows, but that is probably only an advantage if legacy systems maintenance is your aim. Efforts to port it to Linux and BSD and processors other than x86 exist but are not complete, while GCC is already there and has been for years.

I would suggest that if you can support GCC and VC++ you probably have sufficient compiler independence (but recommend you compile with high warning level settings (-Wall -Werrorin GCC and \W4 \Wx in VC++). I think that compiler portability is a trivial issue compared with OS portability, and what you really need to consider is cross-platform library support rather than compiler independent code support.

If however playing with compilers is your thing, also consider the Digital Mars compiler. Like Watcom, this also has commercial compiler heritage, having been the Zortech/Symantec C/C++ compiler in a previous life.

Answer 2

Something watcom has in favor if your a 'haxxor' is the fact you can define out of the ordinary calling conventions using #pragma aux. Other than that, I see no reason to even attempt to use such a dated compiler unless you had horrible hardware restrictions. Imo, there are only 3 to worry about, GCC, ICC and MSVC