* Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx> wrote: > * Ingo Molnar <mingo@xxxxxxx> [2012-02-20 08:38:23]: > > > > > * Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx> wrote: > > > > > The volatiles were added to arch/x86/kernel/kprobes.c because > > > of commit 7115e3fcf45 and 315eb8a2a1b. The volatiles are > > > required because gcc 4.6 gave a warning about the asm operand > > > for test_bit. So the same were added to > > > arch/x86/kernel/uprobes.c. > > > > Seems like a GCC bug - a bogus warning - or does it generate bad > > code as well? > > Yes it is a gcc bug and was fixed by Jakub. > As per Josh, only the first long is output if compiled on the buggy gcc. That's an important piece of information - the more reason to document the quirk. > > In any case, kprobes.c did it correctly, it added the volatile > > *and a comment*, pointing out that it's a GCC bug. No such > > warning was added to uprobes.c, making the volatile look > > entirely spurious. > > okay. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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