Monthly Archives: May 2009

PureBasic 4.31 beta1 released

A new PureBasic release has entered the beta stage. This is a bugfix-only release, there are no new features. The purpose of this release is to give those that only switch to newer releases once the beta-period is over a stable base to work with while the v4.40 release is going through the alpha and beta stages. We tried to focus on the major bugs in the 4.30 release and skip minor issues. Note that some even bigger bugs could not be resolved without major changes to the code and so we postponed these to the next release as well.

You can download it as usual on your user account.

Note: Since there are no new features and we want to get our focus back on the v4.40 release soon, this beta-period will be very short (maybe only one beta release). So if you reported bugs that are now marked as fixed, please test soon to verify that things work as they should now.

The v4.40 release is still a bit away, but we are working very hard on it. The list of new things is quite long again and we still need to work a few things out. Stay tuned.

Windows 95, the comeback !

I know, i know. But there is some stuffs i really hate, and one of them is when you upgrade your compiler version, and suddenly a software stop working on a specific plateform. That happened to the purebasic compiler executable, when we upgraded to VC8. Basically, VC8 adds a dependency to every executable created with it, which is not supported in Windows 95: the famous IsDebuggerPresent() API function (found in Kernel32.dll). So when you launch it on Win95, it just fails at loading time, telling there is a missing symbol. Well, who care about Win95 anymore, you think. I do. For fun. And it’s not a missing symbol (which is useless BTW, and added under the hood by linking libcmt.lib – which is requiered) which will stop PureBasic to work on lovely oldies plateforms.

So the fun began. I asked to my best virtual friend – google – to gently find me a workaround. And guess what ? There was one. But you had to link statically the c runtime and hack a lot with sources. I didn’t want to do that. So i tried to mess with the kernel32 import library (kernel32.lib) to remove the IsDebuggerPresent object. Total failure. Microsoft ‘lib’ tool just see tons on ‘Kernel32.dll’ object in the kernel32.lib when you launch:

prompt> lib /LIST kernel32.lib

Ok. Not very useful to remove a specific object. Sounds like a bug btw…

So i tried with ‘polib’, which comes from PellesC package, without more success. It successfully list the objects name, but unfortunately can’t remove it. Well, i was out of luck. So i created a .def with kernel32 exports and tried to use ‘lib’ to create an import lib. But it doesn’t work as well, for some reason (seems like the lib created isn’t a real dll import lib). Finally i ended up to create a fake kernel32.dll, and reuse the import lib created by the linker. And voilĂ , it worked.. At least VC8 linked and complained about the missing IsDebuggerPresent import, so the hard part was done. Now we just need a small stub in our executable and it’s over. Here is the stub:

// The cool Win95 hack, so the compiler can launch on it, even compiled with VS2005
// Basically, this function is needed by the libcmt.lib/gs_report.obj
BOOL __stdcall _imp__IsDebuggerPresent()
return FALSE;

Timo kindly tested the new build and PureBasic launched and worked correctly on an old Win95. Victory !