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LWN.net Weekly Edition for May 23, 2013
An "enum" for Python 3
An unexpected perf feature
LWN.net Weekly Edition for May 16, 2013
A look at the PyPy 2.0 release
Claiming that it's standard "because GCC does it that way" completely ignores all the other
compilers that do *not* do it that way.
GCC 4.3.0 exposes a kernel bug
Posted Mar 14, 2008 22:26 UTC (Fri) by giraffedata (subscriber, #1954)
I think you got it backward. I claim it's standard because Linux does it that way. Linux is what violates the prescribed standard.
I also didn't state the de facto standard as precisely as I could have, because Linux clearly should change to clear the DF flag. But Gcc should continue to clear it too, because old Linux exists.
Posted Mar 14, 2008 22:42 UTC (Fri) by zlynx (subscriber, #2285)
> But Gcc should continue to clear it too, because old Linux exists.
This does not buy you anything except slowing down all your code unnecessarily. Any user
might use a binary built with some other compiler, like the precompiled commercial MySQL
server, or a game. Software running through Wine is probably built with Visual Studio. A JIT
like Mono or Java might generate code that doesn't reset DF. A developer might be using TCC
for ultra-fast compiles. There is also LLVM: I don't know, but it might not do the DF clear
See what I mean about other compilers? Do you wish to have every one of them also clear DF on
Posted Mar 15, 2008 0:07 UTC (Sat) by nix (subscriber, #2304)
ICC has apparently never cleared DF. I guess nobody's ever tried compiling
programs that make heavy use of asynchronous signal handlers with ICC on
Posted Mar 15, 2008 2:23 UTC (Sat) by giraffedata (subscriber, #1954)
OK, I see your point.
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