Date: Wed, 7 Jul 93 11:38:02 -0500
From: rcharif AT math DOT utexas DOT edu
Posted-Date: Wed, 7 Jul 93 11:38:02 -0500
To: gbm AT ii DOT pw DOT edu DOT pl
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu, michaels AT vsl DOT com DOT au
Subject: djgpp vs watcom
Reply-To: rcharif AT math DOT utexas DOT edu


    Sorry, Watcom is better than GCC (2.3.3) - it generates faster code.
    Watcom optimizer is incredible, sometimes it looks as if the compiler
    ignores all the variable declarations and tries to get the result in
    the best possible way. BUT: You must pay for it quite much.

GCC will never be as fast as native compilers for a given
architecture. It is built to be architecture dependant as it can be.
IT starts by generating an intermediate code of the programs (RTL),
then translates it to assembly language for the target architecture.
This problem affects the i386 architecture more than others due to the
limited number of available registers. The RTL code is organized in a
way that allows the code generator to fit most variables in registers,
and when it runs out of registers, use the memory.

Watcom compiler is probably more optimized for the Intel architecture
at the optimizer level.

    Watcom C/C++ 9.5 has C++.
    It supports an amazing amount of 'OSs': (Ext.) DOS, OS/2 2.x, Windows 3.x, 
    Windows NT, Win32s etc.

Watcom people had the "advantage" of creating their own executable
file format. They choose one that fits well within MS windows 32-bit
limitations. DJGPP uses the BSD a.out format.

Regards,
Rami El-Charif