Mar 00 Factory Floor
Volume Number: 16 (2000)
Issue Number: 3
Column Tag: From the Factory Floor
by Richard Atwell
Codewarrior Release 5.3 Update
Just before the Christmas holiday, Metrowerks shipped its CodeWarrior Release 5.3 Update. We shipped two versions: one that contained pre-built libraries (37MB) and one that didn't (25MB) in order to make the download as small as possible for those with slower connections to the Internet.
We also updated some of our documentation (6MB) but only in PDF format. The update includes the C Compilers Reference, IDE User Guide, MSL C Reference, QuickStart Professional and Targeting Mac OS manuals. The manuals have been updated largely to document the AltiVec support in the tools.
There is also an update to the MetroNub for Java debugger plug-in. This plug-in previously shipped on the CodeWarrior Release 5 Reference CD in the pre-release folder. The MetroNub plug-in that the installer places in your Release 5 Metrowerks CodeWarrior folder is not intended to debug Java anymore. Instead, there is a separate plug-in called the SunJavaPlugin for Java targets. The release notes with the update say:
The only feature that the old Metronub/Java debugger plug-in provides that this new plug-in doesn't is the ability to debug already running Java code without launching the application/applet that uses it from CodeWarrior. In other words, with the new Sun Java debugger plug-in, all Java debugging must originate from the IDE. Attaching to an already running VM process is not supported.
If you don't require this support there's no need to install this extra update. Visit http://www.metrowerks.com/download/ for all the latest tools. The Release 5.3 Update is planned to be the last update before CodeWarrior Release 6.
With the introduction of the IDE 4.0.4 you may have noticed that there are several new plug-ins in the CodeWarrior Plugins:Debugger: folder. These are new symbolics plug-ins and each one contains target-level symbolics support that was previously included in the IDE application itself. Of interest to Mac developers are the SymSymbolics and JavaSymbolics plug-ins.
We've made these changes so development changes to one target don't adversely effect other targets. We hope this will keep the integrated debugger working for the Mac as we make required changes for the other targets that we support.
In addition to these structural changes, the debugger settings target preferences panel has changed in the latest IDE.
Figure 1.new Debugger Settings Panel.
When you open your existing projects you'll get a dialog confirmation that the project needs to be updated to the new settings. When you give the OK, each target will be updated and you'll see a project message such as:
The data for the "Debugger Settings" settings panel in target "PPC Debug MacOS Toolbox" of project "MyProject.mcp" has been updated to the latest version.
The two new options that require updating are Stop at temp breakpoint at application launch and Cache symbolics between runs.
Instead of the old "stop at main" debugger global settings preference, we now allow a target-specific preference to let the debugger stop at the "main" as before (default behavior) or at a user specified symbol.
Simply enter a function name that must be located in the symbolics (main, __start, NewBall) and the debugger will launch your program and stop at this function instead of a hard coded symbol name. This is especially useful because it allows you to start a debugging session and execute all the way until you reach a location such as the function you are currently debugging, then halt.
Caching symbolics between runs is what the integrated debugger always used to do. Our debugger used to keep symbolics loaded until a new build was created or the project was closed. With our MPW command line tools this posed a problem if the user built them, debugged, and then attempted to build with them again without closing the project: the tools could not write some of the output files since they were still being used by the debugger.
With this option off, symbolics are discarded between runs, which frees the symbolic files so that external programs may modify them. The further benefit is that if you were to kill and restart your program, symbolics would be discarded and reloaded. That could take some time if the SYM file is large.
Compilers And MSL
We shipped MSL 5.2 and new 2.3.2 compilers with the Release 5.3 Update. There are many new language features available in the front end and improvements to the PowerPC backend.
Here are some front-end highlights:
- Support for the ISO C++ section 16.8 value for the predefined macro "__cplusplus". This is set to "199711L" to indicate conformance with the ISO C++ specification.
- Support for #pragma fullpath_prepdump on|off|reset (default off). This option can be used to show the full path of any included files in the comments in a preprocessor dump. When turned off, only the filename portion of the path is shown.
- Support for #pragma line_prepdump on|off|reset (default off). This option can be used to uncomment the "#line ..." directives in a preprocessor dump. This option it will also preserve the vertical line spacing by inserting empty lines.
- "#pragma gcc_extensions on" now allows automatic struct/array variables to be initialized with non-const values, such as function parameters. (non-ANSI C)
- #pragma warn_no_side_effect on|off| reset (default: off)
- #pragma warn_resultnotused on|off|reset (default: off)
- __option(<x>) will now return 'false' instead of an error message if <x> is an unknown option/#pragma.
- #pragma opt_strength_reduction_strict on|off|reset (default: off). This option can be used to disable strength reduction optimizations that could be unsafe because the induction variable has an unsigned type smaller than the pointer type. Previously, this option was controlled solely by the ANSI strict setting.
Some PowerPC backend highlights:
- Support #pragma function_align 4|8|16|32|64|128|reset allows specifying of the alignment of a function.
- AltiVec constants are now pooled.
- #pragma altivec_vrsave allon is now supported. It sets VRsave assuming that all AltiVec registers are in use, best used with "#pragma altivec_vrsave off" so only the parent routine updates the vrsave register.
- Added "machine 7400" directive to inline assembler
Mac OS Support
We're continually updating the support folders new that we ship CDs less often. With the Release 5.2 Update we made several changes to MacOS Support:
- Updated MacHeaders so they can be compiles with ANSI Strict ON. This usually means removing the // C++ style comments and replacing them with the /* C style comments.
- Added a stub library for the PLStringFuncs that exist within StdCLib.
- Added some common MPW files that are not part of Universal Interfaces.
- Replaced fp.h with the modified Pro4 version that fixed problems when including cmath and fp.h in the wrong order.
As always, we welcome your feedback on any subject. Contact us through our newsgroup or send us email directly using the addresses below.
Richard Alexander David Atwell started at Metrowerks in 1998 when he signed up to join the ranks of those who use CodeWarrior to write CodeWarrior. If you are interested in doing the same you can reach him at firstname.lastname@example.org.