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GCC 4.3.0 Exposes a Kernel Bug
ohxten sends news from earlier this month that GCC 4.3.0's new behavior of not clearing the direction flag before a string operation on x86 systems poses problems with kernels — such as Linux and BSD — that do not clear the direction flag before a signal handler is called, despite the ABI specification.
That's what happens when you don't clear that STD...
from 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
to 45 2F 6E 40 3C DF 10 71 4E 41 DF AA 25 7D 31 3F
Better than a general fault.
GCC 4.3.0's new behavior of not clearing the direction flag before a string operation on x86 systems poses problems with kernels -- such as Linux and BSD -- that do not clear the direction flag before a signal handler is called, despite the ABI specification.
Oh my GOD! If this is true, that means- that means-- it... the-
Uh, what does it mean exactly?
1991 was a long time ago. Linux is old.
Help stamp out iliturcy.
It's like you got a bunch of cars at a stoplight and you want to walk by each to panhandle for money but instead of starting at the first car in line and the walking down to the back, you start at the first then head out into cross traffic and get run over and something crashes.
I'm a consultant, and I'm wondering what the billing rate times a fuckton is going to total out to.
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
Is a fuckton more or less than a metric assload?
SJW n. One who posts facts.
Hehe, I'm going to try that approach the next time I'm assigned a bug: "No, it's not the code that's wrong, it's the specification."
"Give me six lines of C++ code written by the most competent programmer, and I will find enough in there to hang him."
Information wants to be free. Bandwidth wants to cost money.
What the hell are you talking about?
You two are on different wavelengths. Consider that before you open your little can of whoop-ass next time. BTW, your attitude is a real turn-off which makes hearing your point much more difficult.
On the other hand: the instructions affected by this aren't used very much, so if you want optimizations, a good candidate would be to not clear the flag unless it is needed. If the ABI were simply changed to allow this, no existing code would break (obviously), and future code could both conform to the new ABI *and* avoid the overhead of unnecessary instructions to clear the flag when it is not being used.
I suppose the only barrier to this optimization would be the political effort needed to get everyone to agreee to change the ABI.
at least nothing of value is affected.
Do you even lift?
These aren't the 'roids you're looking for.
From http://en.wikipedia.org/wiki/GNU_Compiler_Collection:
Perhaps the error in your assertion is a side effect of an uncleared direction flag.
It depends, the US Fuckton is less than a metric assload, but the Imperial Fuckton, previously used in the UK, was more.
NB The use of 'assload' without the 'metric' qualifier is discouraged, the customary US assload being a much greater mass.
Well, they could always link again in the dupe.
Slow down, cowboy! It has been 4 hours since you last posted. You must wait another few hours.
You lose one CPU cycle ?
Religion is what happens when nature strikes and groupthink goes wrong.
I just heard that this has seriously set back the release date of Duke Nukem Forever!