Watcom C/C++ compiler

Open Watcom

Original author(s)	Watcom Sybase SciTech Software
Developer(s)	Open community
Initial release	January 8, 2003; 8 years ago (2003-01-08)
Stable release	1.9 / June 2, 2010; 16 months ago (2010-06-02)
Development status	Active
Operating system	Cross-platform
Size	73.8 Mb
Type	Integrated development environment
License	Sybase Open Watcom Public License version 1.0
Website	www.openwatcom.org

The Watcom C/C++ compiler is esteemed amongst DOS developers by the high execution speed of the compiled code it produces and for having been one of the first compilers to support the Intel 80386 "protected mode"^{[citation needed]}. In the mid-1990s, some of the most technically ambitious DOS games such as Doom, Descent and Duke Nukem 3D were built using Watcom C.^[1]

Though no longer sold commercially by Sybase, the Watcom C/C++ compiler and the Watcom Fortran compiler have been made available as the free and open source^[2] Open Watcom package with the assistance of SciTech Software. The code is portable and, like many other open source compiler projects such as GCC or LCC the compiler backend (code generator) is retargetable. The compiler can be operated from, and generate executable code for, the DOS, OS/2, Linux and Windows operating systems. It also supports NLM targets for Novell NetWare. There is ongoing work to extend the targeting to Linux^[3] and modern BSD (e.g., FreeBSD) operating systems, running on x86, PowerPC and other processors. The Open Watcom C/C++ version 1.4 release on December 2005 introduced Linux x86 as an experimental target, supported from NT or OS/2 host platforms. There is code for an abandoned QNX version, but libraries necessary for it to be compiled could not be released as open source.^{[citation needed]} The current stable version 1.9 was released in June 2010.^[4]

Release history

The Open Watcom Wiki has a comprehensive history.^[1]

Date	Product	Notes
1984	Waterloo C for S/370
1985		Work on current code generator codebase started
1988	Watcom C 6.0	DOS host and target only Included a debugger and full set of runtime libraries Generated better code than other compilers at the time
1989	Watcom C 7.0
1989	Watcom C 7.0/386	First 32-bit version, DOS host and target only Supported Phar Lap DOS extender Did not come with a linker or debugger
1990	Watcom C 8.0
1990	Watcom C 8.0/386	Added linker, librarian, debugger, and profiler Added graphics library
1991	Watcom C 8.5
1991	Watcom C 8.5/386	Shipped with DOS/4GW Windows 3.0 supported (Win386 extender) Unicode support OS/2 hosted executables added
1992	Watcom C 9.0
1992	Watcom C 9.0/386	OS/2 2.0 host and target support 486 optimizations Based pointer support
	Watcom C 9.01/386	Windows 3.1 support
1993	Watcom C/C++ 9.5
1993	Watcom C/C++ 9.5/386	C++ compiler added Pentium optimizations Windows NT host and target support
1994	Watcom C/C++ 10.0	MFC included Precompiled header support 16-bit and 32-bit tools merged into single package Redesigned debugger C++ class browser added Windows resource editors added Graphical IDE for Windows and OS/2
1995	Watcom C/C++ 10.5	Native C++ exception handling on OS/2 and Win32 Windows 95 and NT 3.5 support TCP/IP remote debugging
1996	Watcom C/C++ 10.6	Structured exception handling in C Improved compatibility with Microsoft compilers
1997	Watcom C/C++ 11.0	Namespace, RTTI, and new style cast support in C++ compiler 64-bit integer support Multi-byte character support in libraries Incremental linking support COFF and ELF object file support in linker and librarian Microsoft clone tools added DLL based tools for better IDE integration
1998	Watcom C/C++ 11.0B
1999		Sybase issues end-of-life notice for Watcom C/C++ 11.0
2000		Sybase announces open sourcing of Watcom tools
2001-09-27	Watcom C/C++ 11.0c Beta
2002-12-21	Watcom C/C++ 11.0c
2003-01-28	Open Watcom 1.0
2003-08-12	Open Watcom 1.1
2004-01-07	Open Watcom 1.2
2004-08-03	Open Watcom 1.3
2005-12-14	Open Watcom 1.4
2006-04-26	Open Watcom 1.5
2006-12-15	Open Watcom 1.6
2007-08-18	Open Watcom 1.7
2007-10-23	Open Watcom 1.7a
2009-02-21	Open Watcom 1.8
2010-06-02	Open Watcom 1.9

Compatibility with other compilers

Open Watcom's syntax supports many conventions started by other compilers (such as Microsoft's and Borland's), including differing conventions regarding (for instance) the number of leading underscores on the "asm" tag. Code written for another compiler will often compile with Watcom's, but it's usually a better idea to write in standard-compliant C or C++ than to write code for a compiler.

See also

• Open Watcom Assembler

References

1. ^ ^{a b} History - Open Watcom. OpenWatcom.com wiki.
2. ^ Source code. OpenWatcom.org FTP server.
3. ^ Installing Open Watcom on Linux - Open Watcom. OpenWatcom.org wiki.
4. ^ "Latest Release (June 2010) - Open Watcom". OpenWatcom.org wiki. http://www.openwatcom.org/index.php/Main_Page#Latest_Release_.28June_2010.29. 

External links

• Open Watcom website
• Paul Hsieh. (Revision 4.12, 2008-05-08). "The WATCOM C/C++ Programmer’s FAQ". http://www.azillionmonkeys.com/qed/watfaq.shtml. Retrieved 2008-10-07. 
• Rick Grehan (October 1994). "Watcom C/C++ Gets a New Face". BYTE 19 (10): 111. Archived from the original on 1997-07-12. http://replay.web.archive.org/19970712221411/http://www.byte.com/art/9410/sec12/art5.htm. Retrieved 2011-05-14.