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by kjhgfghjm 5570 days ago
Adobe had a bug which worked because of a Bug in memcpy(), the bug was fixed and Adobe's code broke.

win95 had a similar one with the game Civilisation, they actually put code into win95 to detect the game and change the way the OS worked - doesn't sound like a good solution
3 comments
ot 5570 days ago
I guess you are referring to this:

> I first heard about this from one of the developers of the hit game SimCity, who told me that there was a critical bug in his application: it used memory right after freeing it [...] the Windows developers, who disassembled SimCity, stepped through it in a debugger, found the bug, and added special code that checked if SimCity was running, and if it did, ran the memory allocator in a special mode in which you could still use memory after freeing it.

(from http://www.joelonsoftware.com/articles/APIWar.html )

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azernik 5570 days ago
Read the spec for memcpy: memcpy's behavior on overlapping memory regions is undefined - not "required to corrupt memory", but undefined. Changing memcpy from not breaking on overlapping memory regions to breaking does not fix any bugs.

Adobe should not rely on non-spec-defined behavior, but there's no reason why glibc <i>should</i> be making this change without making a major version number change.

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flomo 5570 days ago
What? The whole raison d'être of Windows 95 was backwards-compatibility with primordial PC junk. The entire thing was a hack from top-to-bottom, far beyond a workaround for a particular game.

Also, to quote Linus:

"And what was the point of making [an OS] again? Was it to teach everybody a lesson, or was it to give the user a nice experience?"

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