Messages in this thread | | | From | Joe Buck <> | Subject | Re: [PATCH] C undefined behavior fix | Date | Wed, 2 Jan 2002 12:13:34 -0800 (PST) |
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> Okay, here's a summary of all of the options we have: > 1) Change this particular strcpy to a memcpy > 2) Add -ffreestanding to the CFLAGS of arch/ppc/kernel/prom.o (If this > optimization comes back on with this flag later on, it would be a > compiler bug, yes?) > 3) Modify the RELOC() marco in such a way that GCC won't attempt to > optimize anything which touches it [1]. (Franz, again by Jakub) > 4) Introduce a function to do the calculations [2]. (Corey Minyard) > 5) 'Properly' set things up so that we don't need the RELOC() macros > (-mrelocatable or so?), and forget this mess altogether.
2) will prevent any future gcc from ever assuming it can transform the strcpy into anything but a call to strcpy, or assume anything about the semantics of strcpy. Be careful with 3), as trying to fool the optimizer is likely to be only a temporary solution (meaning that the kernel people will return to flame the gcc people when the optimizer gets changed again).
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