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On Sat, 31 May 2008 02:17:15 +0200 |
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Luca Barbato <lu_zero@g.o> wrote: |
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> Ciaran McCreesh wrote: |
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> > Linking with as-needed is the stage in which the elimination occurs, |
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> > and as-needed is the cause of the elimination. So yes, it is |
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> > related. |
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> |
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> The linker just does bookkeeping, if there aren't symbols used, the |
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> library won't be in the list. |
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Which is where the design flaw is -- as-needed incorrectly assumes that |
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the only type of dependency between shared objects is a name |
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dependency. This isn't true with C++ static initialisers. |
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|
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> >> Still, PE and ELF are older than the first C++ spec so, IFF your |
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> >> reading of this chapter is correct, C++ is broken by design. |
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> > |
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> > Not at all. Read "The Design and Evolution of C++", and you shall |
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> > see that requiring changes to the linker where necessary for |
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> > sensible behaviour was considered acceptable, and with good reason. |
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> |
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> As in "we have a square wheels, let's make routes for them"... |
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|
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More like "getting the linker right is important enough to us that |
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we'll pester people to make their wheels at least octagonal rather than |
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the current square". Unfortunately, as-needed is moving back to square. |
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> Anyway is the book a standard? Is it available as pdf so you can |
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> point me the exact paragraph? |
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The book is an explanation of why the standard is the way it is. You |
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can find it at your local library. |
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Whilst we're on the subject... You'll note that as-needed overrides |
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explicit instructions from the programmer. When you say "link A to B", |
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you aren't say "link A to B unless you feel like not doing the link". |
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Unfortunately, the ricers shoving as-needed upon everyone aren't smart |
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enough to fix libtool, which is the real problem here, so they go for |
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the thing they think they understand instead, without thinking the |
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implications through -- as-needed, like fast-math, is for programs |
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explicitly designed for it, not for universal use. |
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|
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-- |
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Ciaran McCreesh |
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