Q:  Which PC C/C++ compiler is best and what should I buy?

A:  This is perhaps the commonest of Frequently Asked Questions (FAQ's),
especially by beginning C'er. The honest answer is that there is no "best"
compiler and what may be best for you depends to a large degree on what
you'll be using it for. The PC C/C++ compiler market is quite brutal and the
companies that have survived have done so because some number of people think
each of them makes the "best" compiler.

    With the preceding caveat in mind, following are some summaries of the
current crop of C/C++ compilers with some of their strengths and weaknesses.
Additional recommended reading are the C/C++ compiler reviews appearing in PC
Magazine. PC Mag's reviews for many years were highly slanted and suspect,
but, in recent years, have become commendably objective and even-handed.


MIX POWER C
-----------

Power C is the least expensive PC C compiler on the market. The compiler
itself is $20, and an additional $30 will buy their source-level debugger
along with the complete library source code with an assembler.

So, what's the catch?

None, actually. Power C is a quite decent and ANSI-conforming compiler which
compiles relatively tight, fast code relatively quickly. It's biggest
drawback is its use of a non-standard object file format which obviates
object-level compatibility with any other compiler using Microsoft/Intel
standard object file formats. Another problem is lack of support from 3rd
party library vendors. Although Mix sells a wide range of libraries
themselves, it's difficult to convince a vendor to produce a $100 add-on
library for a $20 compiler.

On the plus side, Power C comes with the best user's manual for students in
the business. The beginner's tutorial section has enabled many beginning C
programmers to get up to speed without spending another dime on any other
textbooks. Should you want more instruction, Mix sells a package including
Power C with the library source and debugger along with the book "Master C"
for only $60.

Power C's primary technical claim to fame is its floating point which
challenges the industry leader, Watcom, in many cases. It's also the only
remaining C compiler which can run effectively on small or older machines
without extended memory (SC++ can also, but is limited to *very* small
programs).



MICROSOFT VISUAL C++ (VC++)
---------------------------

Microsoft's professional compiler now comes in two versions with the same
name but different version numbers.  Version 1.52 is the current 16 bit
compiler, and supports DOS and Windows.  With some care (and libraries from
MS C 6.0) people have gotten it to produce programs for OS/2 as well, but
this proposition is not for the faint of heart.

Visual C++ 2.x supports only Win32 targets.  (Windows NT and Windows 95)
It bears a reasonable similarity to the 16 bit compiler, but many of the
ancillary tools have changed, particularly those that deal directly with
executables, which isn't surprising since the executables themselves have
changed considerably.

On the plus side, VC++ is an excellent C++ compiler and generates executables
which may not always be smaller than Borland, but usually execute faster.
Microsoft's C compilers are still the standard for PC C compilers and it
shows in the ready availability of 3rd party libraries supporting it. Support
for Windows programming is excellent with tools only rivaled by SC++ (which is
shipped with licensed copies of the MFC class library).

Compile times with full optimization are still quite sluggish, but using the
quick compile option can be provide acceptable results.  The 32 bit compiler
has no explicit quick compile option, but compile times with optimization
turned off are fairly reasonable.



BORLAND C++ (BC++)
------------------

BC++ carries on Borland's tradition of providing excellent bang for the buck.
The latest release (4.5) of their professional compiler is an attractive
alternative to shops also considering VC++. BC++ isn't as demanding as VC++
but still requires considerable resources.  However, the 32 bit compiler is
one of the few 32 bit versions to still run under DOS, reducing its hunger for
memory considerably compared to VC++ and SC++, which both require 16 Megs for
32 bit compilation.  The present Windows development tools are roughly on a
par with those from Microsoft and Symantec.  For unknown reasons, the 32 bit
compiler is roughly twice as fast as the 16 bit compiler, given sufficient
memory.

Borland's tools are uniformly excellent, but the compiler still suffers a bit
in comparison to the industry's technological leaders, Microsoft, Watcom, and
Symantec - although the gap is closing. As with VC++, it's an excellent C++
compiler and enjoys widespread support among 3rd party library vendors. Like
all Borland compilers, ease of use was a design priority, all oriented to the
excellent IDE.

BC 4.5 followed fairly closely after the (disastrous) release of BC 4.0.
While Borland loyalists still miss the DOS IDE, in most other areas, the
major problems with BC 4.0 have been ironed out and Turbo Profiler, which was
left out of BC 4.0, has been added back in.  The single greatest lack at this
point is likely the DOS based IDE.  At this point, a Win32 and/or OS/2 text
mode IDE might be a better choice.  OTOH, there are many excellent text
editors capable of far more than the DOS IDE ever dreamt of.

The final consideration in choosing Borland's tools is the financial soundness
of the company.  Around the beginning of 1995, Borland seemed almost certain
to be gone by the end of the year.  However, the recent release of Delphi has
apparently been almost as good as BC 4.0 was bad, and their finances seem less
a worry at the moment.



TURBO C++ (TC++)
----------------

TC++ is to Borland's C++ compiler targeted at the hobbyist market. The latest
version (TC++ 3.1) raised quite a stir when Borland released it requiring at
least a 286 processor and 1 Mb of *available* extended memory above the
normal 640K DOS limit.  Many hobbyists running on older XT's, or machines
without the excess memory capacity have therefore failed to upgrade to the
new release.

If you have the machine to support it, TC++ has the usual Borland attributes
of extreme ease-of-use, attractive Integrated Development Environment (IDE),
and good supporting tools. Based on the facts of BC++ 4.0 cited above, it has
become the compiler of choice for many Borland loyalists.


SYMANTEC C++ (SC++)
-------------------

Symantec C++ (nee Zortech C++) was the industry's first C++ compiler, but fell
behind in tracking the C++ language spec. Bought out by Symantec in 1991, the
C compiler was always excellent and now its C++ compiler rates among the best.

SC++ supports DOS, Mac, Unix, Win32s, and NT (OS/2 was supported in previous
Zortech releases and may be again) using an extremely powerful new object-
oriented Windows-hosted IDE. It includes excellent libraries and add-ons
including a TSR library, swapping spawn functions, a royalty-free 32-bit DOS
extender, and an excellent set of ancillary C and C++ tools libraries
including MFC 2.0 as previously noted. SC++ can generate true 32-bit code and
has a switch for generating Pentium code. At the same time that Symantec
bought Zortech, they also bought Multiscope, whose debuggers are included in
the package. As with VC++, SC++ includes excellent tools for quickly
developing Windows applications.

SC++ has always been in the forefront of optimizer technology along with
Microsoft and Watcom. A major feature is full IEEE-754 and NCEG (Numerical C
Extensions Group (an ANSI working committee trying to make C a suitable
replacement for FORTRAN) compatibility.

The only negative for the current release is a poor reputation which arose
largely during the period following the Symantec acquisition of Zortech. As
of version 6.1, the bugs were mostly fixed. Support of DOS graphics was also
dropped, but an updated version of the excellent Flash Graphics package
shipped with the Zortech versions is available from FlashTek, which also
supplies improved versions of the 32-bit DOS extender and the pre-Symantec
debugger. The current 7.0 release fixes almost all residual bugs and is
significantly enhanced in the area of portability, supporting features of
other DOS compilers such as the _interrupt keyword.

One caveat - if you have any version prior to the 6.1 release, be sure to
upgrade!


WATCOM C/C++ (WC++)
-------------------

Watcom has traditionally been the technological industry leader, performing
feats of optimization and floating point speed other vendors only dreamt of.
The cost has been compile speed, which has been described (somewhat unfairly)
as glacial. For all its technical excellence, WC++ is still a niche market
compiler like SC++. As such, it's 3rd party support is poor, but many have
found that Microsoft C libraries can be made to work with WC++, often with
nothing more than recompilation. As other compilers (most notably VC++ and
SC++) have advanced, WC++'s technological lead has diminished and even been
reversed for some applications. Like SC++, and unlike BC++ and VC++, WC++
provides documented support for embedded systems work, although not to nearly
the same degree as Metaware (see below).

Also, like SC++, WC++ supports 32-bit code generation. WC++ is the compiler
of choice for many OEMs, such as Novell, who want only the best supporting
code for their products. MSC/VC++ compatibility is excellent, but watch out
for Watcom's sensitivity to proper _cdecl declarations, implemented in Watcom
via a pragma rather than as a built-in language feature. Watcom sells both
16- and 32-bit versions of its C/C++ compiler. The best deal is to buy the
32-bit compiler and then purchase the 16-bit upgrade pack.

Where Watcom really shines is its support for a multitude of environments
with the same compiler(s). Supported are DOS, Win3.1, Win32s, NT, OS/2 (1.x &
2.x), Netware 386, AutoCAD ADS, QNX, Phar Lap and Rational DOS extenders.
With such a bewildering array of targets, compilation is relatively
straightforward but the linker has a steep learning curve.

Watcom remains the only one of the "big name" compilers to not offer an IDE,
if that's important to you or you don't own a "real" programmer's editor.


METAWARE HIGH-C/C++ (HC++)
--------------------------

HC++ is the darling of some segments of the embedded systems market. As such,
it's a lot like WC++, only not quite as good and a lot weirder since it
offers detailed control over every aspect of the executable. Most WC++
comments apply, except for the ones relating to quality of generated code.
HC++'s code is quite good, but seems to be showing its niche market
orientation (any one remember Manx Aztec C?)


TOPSPEED C/C++ (TSC++)
----------------------

TSC++ has had a rocky life, getting off to a late start in the market and
never having really quite caught on. Originally, TSC++ was a Turbo C clone
which shared tools and environments with its sister Modula-2 compiler. More
recent versions have extended this by using a modular approach with an
environment supporting "plug-in" compilers for various languages which can
all be used together. The company was recently acquired by Clarion.

TSC++'s undisputed biggest strength is its smart linker and various features
added to facilitate mixed-language programming (Modula-2, for example,
supports multi-threaded code). Using this technology, you can count on TSC++
to almost always produce the smallest executables for a given piece of source
code. The library, written almost exclusively in assembly, is also excellent
and contributes to the frugal use of run-time memory. Unfortunately, the code
generated by the compiler - even with full optimization - is typically not
of the same quality as the library modules.

Drawbacks include almost non-existent 3rd party support and the pervasive IDE
which feels more at home to Modula-2 programmers than C programmers.


GNU C/C++ (GCC, G++; also DJGPP, EMX)
-------------------------------------

Available from the Free Software Foundation (FSF), GCC and G++ are two of
only three compilers listed here available for free (the other is Micro-C).
Originally written for Unix systems, there are several DOS and OS/2 ports
available. All of the DOS ports require some sort of DOS extender technology
built-in in order to work in DOS's limited memory. The most popular of the
DOS ports is DJGPP. OS/2 ports obviously don't share this limitation. The EMX
port for OS/2 is among the best and is quite popular among OS/2 programmers.
Along with SC++, WC++, and HC++, the gnu compilers round out the list of full
ISO/ANSI/ARM compilers with explicit support for embedded systems.

Performance is decent, but not earth-shattering, and executables - especially
small utilities - tend to exhibit some bloat. This may be overcome by using
some non-standard compiler features unique to FSF compilers at the expense of
portability.

All GNU software carries the FSF's "GNU General Public License". This is
their infamous "copyleft" license that guarantees their software tools remain
free, yet imposes restrictions on redistribution and commercial distribution
of the GNU tools and software developed with them. If you plan to use one of
these to write commercial code, be sure and read the license agreement *very*
closely.  Note that simply producing an executable with the compiler does not
subject the resulting program to copyleft, but use of GNU's run time library
code subjects the program to their special library license, which is separate
from the standard GNU license.  Be *sure* to get the correct license and read
it carefully before deciding on GCC/G++ for commercial use.  In the case of
DJGCC, the DOS extender used is subject to another license of its own.


DUNFIELD MICRO-C
----------------

There have been many "small" or "tiny" C's over the years, some useful for
teaching the rudiments of compiler construction, others not much use for
anything. Small C's typically lack structs, unions, bit fields, and even long
integers.

Why bother listing this one then?

First of all, Micro-C is an evolving product which, as of version 3, now
includes many features such as structs and unions not normally associated
with small C's.

Secondly, Dave Dunfield recently made the DOS version of Micro-C freeware.
You can use it without restriction or licensing fees to create DOS programs.

Third, the source code (available when you register the shareware version) is
quite decent and really can teach you something about compiler internals. But
Micro-C is genuinely useful for a lot more reasons.

Finally, the PC library includes support for writing TSR's, interrupt-driven
serial I/O, and screen windowing. Amazingly, it also sports an optimizer, but
requires MASM or equivalent for compiling PC applications.

How does Dave provide such a nifty tool for free? Simple - he makes his money
off of Micro-C by producing cross-assemblers for a variety of microprocessors
and provides plug-in code generators for his C compiler to use with those
chips as well. The 80x86 version comes ready to compile either PC or embedded
code.

Supporting small and tiny model only, Micro-C executables are phenomenally
small. "Hello world" programs that run 5-6K on other compilers run under 600
bytes when compiled with Micro-C.

One other point needs to be mentioned with respect to Micro-C...  Although it
is *a* small C, it has no code commonality with *the* Small C from the book
of the same name. This is important since there are a number of variants of
Small C available, all not much better than the original.  Micro-C, OTOH, was
written by Dave Dunfield completely from scratch and is a *much* better
designed piece of code and certainly much more instructive to fledgling
compiler writers. His better design is evinced in code quality and execution
speed.


PCC
---

The Personal C Compiler is available as shareware. It used to be marketed as
the deSmet C compiler and had a generally good reputation for quick compile
times and tight code. Unfortunately, the product hasn't been seriously
upgraded in quite a while and can't stand too much comparison. It's horribly
non-ANSI compliant, has a weaker set of library functions than Micro-C,
features non-standard file formats, and is generally incompatible with most
published C code.  Even Micro-C, which makes no claim to ANSI compliance, is
still considerably closer to it than PCC.  The current version of Micro-C
accepts function prototypes, likely the single most important addition made
to C in the ANSI standard.

If price is your concern, Mix Power C costs less to buy than PCC does to
register and offers better performance along with the ANSI compliance that
PCC lacks.  If you plan on using an unregistered copy, Gnu C/C++ is vastly
superior and is legally free. If you're attracted to its tight, fast code and
can live with quirks and without ANSI compliance, go with Dunfield Micro-C.


Q.  Do have any samples?

A:  The following program was compiled using several DOS compilers with the
    results as noted below. The compilers tested are noted in the executable
    program's name as follows:

      Suffix      Compiler                Notes
      ------      --------                -----
      _b45        Borland C 4.5
      _b31        Borland C 3.1
      _g32        gnu C (DJGPP 1.12M2)          GO32 32-bit DOS extender
      _mc         Dunfield Micro-C 3.13
      _ms         Microsoft C 8.0               Part of Visual C++ 1.5
      _pc         Mix Power C 2.2
      _sc         Symantec C 7.0
      _s32        Symantec C 7.0                DOSX 32-bit DOS extender
      _wc         Watcom C 10.0
      _w32        Watcom C 10.0                 DOS/4GW 32-bit DOS extender
      _zc         Zortech C 3.0r4
      _z32        Zortech C 3.0r4               DOSX 32-bit DOS extender

    All executables were compiled with maximum optimization and with other
    options (e.g. no exception handling for Borland 4.5) to assure minimum
    size of the executables. The results for Zortech and Borland are for
    comarison since both are several revision obsolete (however they do
    highlight the fact that if all you want to do is compile straight C code,
    sometimes the latest isn't always the greatest). The test file was
    selected as an example of a minimally useful standard C program. Some
    coding peculiarities were introduced to accomodate some non-standard
    features of the Micro-C library.

    The program listing is followed by execution and compile times. The
    machine used for the test was a 486/DX50 using Golden Bow's Vcache. Due
    to the presense of the cache and the small size of the program, the
    execution timings are probably only grossly representative. The timings
    for the DJGPP-compiled test includes timings for both the compilation and
    COFF-to-.EXE conversion required to produce a stand-alone executable. The
    compilation time listing for WCL386 is for the Watcom-compiled version
    using the DOS/4GW 32-bit DOS extender.
  
----[ Size.C ]----------------------------------------------------------------

#include <stdio.h>

#ifndef __MICROC__
 #include <string.h>
#endif

main(int argc, char *argv[])
{
      char buf[80], *ptr;
      FILE *me;

      if (NULL == (me = fopen("size.c", "r")))
      {
            fputs("Can't open SIZE.C\n", stderr);
            return -1;
      }
      while (1)
      {
            if (NULL == fgets(buf, 80, me))
                  break;
            for (ptr = buf + strlen(buf) - 1;
                  ptr >= buf && *ptr == '\n'; --ptr)
            {
                  *ptr = '\0';
            }
            printf("%s\n", buf);
      }
      return 0;
}

----[ Dr.Out ]----------------------------------------------------------------

 DR 3.00á 
Disk vol "STACVOL_DSK"
Directory of D:\BINK\CODE\WIP
12 Files totalling 192,477 bytes
602,865,664 Bytes free

Size_mc  Com       2,105  ..a.rwx  20 Nov 95   9:59:42  < Micro-C 3.13
Size_zc  Com       8,035  ..a.rwx  20 Nov 95   9:59:00  < ZTC 3.0r4
Size_ms  Com       8,049  ..a.rwx  20 Nov 95  10:09:50  < MSC 8.0
Size_b31 Com       8,776  ..a.rwx  20 Nov 95  10:11:24  < BC++ 3.1
Size_wc  Com       9,318  ..a.rwx  20 Nov 95  10:03:46  < WC 10.0
Size_sc  Com      10,528  ..a.rwx  20 Nov 95  10:04:48  < SC++ 7.0
Size_b45 Com      11,216  ..a.rwx  20 Nov 95  10:07:20  < BC++ 4.5
Size_pc  Exe      13,312  ..a.rwx  20 Nov 95  10:12:40  < Mix Power C 2.2
Size_w32 Exe      25,994  ..a.rwx  20 Nov 95  10:21:44  < WC/DOS 4G/W
Size_z32 Exe      27,941  ..a.rwx  20 Nov 95  10:17:44  < ZTC/DOSX
Size_s32 Exe      29,149  ..a.rwx  20 Nov 95  10:18:42  < SC++/DOSX
Size_g32 Exe      38,054  ..a.rwx  20 Nov 95  10:23:44  < DJGPP 1.12M2

----[ Execution times ]-------------------------------------------------------

SIZE_WC     Elapsed time = 0.116001 Seconds     < WC 10.0
SIZE_MS     Elapsed time = 0.116579 Seconds     < MSC 8.0
SIZE_B31    Elapsed time = 0.121079 Seconds     < BC++ 3.1
SIZE_PC     Elapsed time = 0.127011 Seconds     < Mix Power C 2.2
SIZE_ZC     Elapsed time = 0.218889 Seconds     < ZTC 3.0r4
SIZE_SC     Elapsed time = 0.221269 Seconds     < SC++ 7.0
SIZE_MC     Elapsed time = 0.226919 Seconds     < Micro-C 3.13
SIZE_B45    Elapsed time = 0.232461 Seconds     < BC++ 4.5
SIZE_Z32    Elapsed time = 0.233987 Seconds     < ZTC/DOSX
SIZE_G32    Elapsed time = 0.406291 Seconds     < DJGPP 1.12M2
SIZE_S32    Elapsed time = 0.461156 Seconds     < SC++/DOSX
SIZE_W32    Elapsed time = 1.299404 Seconds     < WC/DOS 4GW

----[ Compile times ]---------------------------------------------------------

PC (Mix Power C) 2.2    1.505081 Seconds
CC (Micro-C) 3.13       1.843561 Seconds
ZTC 3.0r4               1.948132 Seconds
SC 7.0                  3.002091 Seconds
BCC 4.5                 4.108201 Seconds
BCC 3.1                 4.586260 Seconds
WCL 10.0                5.669630 Seconds
WCL386 10.0             6.342555 Seconds
CL (MSC) 8.0            6.697373 Seconds
GCC (djgpp) 1.12M2      8.287935 Seconds

----[ finis ]-----------------------------------------------------------------
