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If Coro causes segfaults a lot on calls to libc functions, the cause is |
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probably a glibc compiled for i386 and kernel 2.2. |
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Glibc contains a bug that causes any program linked against pthreads AND |
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using coroutines (of any kind, not only Coro, but including most userspace |
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thread libraries like gnu-pth) or alternate stacks to segfault on calls to |
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pthread functions. And glibc happens to do a lot of these calls. |
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(Even if you perl is not compiled against pthreads, Time::HiRes links |
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against -lrt, which drags in pthreads. The same is true for other modules, |
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so watch out). |
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The bug is rather difficult to fix. This is not a problem, however, since |
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glibcs compiled for linux-2.4 use a much more efficient method to locate |
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their data, which happens to work with coroutines. |
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So the easy fix is to install a libc which was compiled for linux-2.4, |
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using the "--enable-kernel=2.4 i586-pc-linux-gnu" configure options. |
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|
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WARNING: This libc will no longer run on linux-2.2 or lower! |
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UPDATE: I am no longer able to compile glibc-2.3.2 in this way. The reason |
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is most probably that the glibc folks work on an enhanced thread local |
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storage facility, and it might be that you need a 2.5 or 2.6 kernel to |
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make it work. Glibc-2.3.1 works fine, though. |
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UPDATE: Time::HiRes in current perl snapshots does no longer link against |
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-lrt. That still means you need to patch it until 5.9.x gets out. |
