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On Thursday, 19 December 2013 10:18:55 CEST, Michał Górny wrote: |
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> Would it be possible to have a consistent ABI for both C++03 and C++11? |
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> The simpler changes like adding new fields can be backported quite |
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> easily (even if it would mean having dummy fields in C++03), I have no |
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> idea about the more complex changes. |
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I don't know, but from a bystander's point of view, I surely hope that it |
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will be possible. Otherwise there would be no option but providing a |
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multilib-like setup for C++11, after all. |
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Some messages on gcc's ML indicate that there are software vendors who are |
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*very* afraid of doing the SONAME change again. Given that C++11 forbids a |
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refcounted std::string while libstdc++ currently use just that for its |
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implementation, I suspect that the upstream developers have a very |
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interesting problem to solve. (And there's much more.) |
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It is pretty clear to me that even the gcc people have not reach a |
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consensus on how the ABI of the standard library will look like in 4.9, so |
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maybe it is premature for us to talk about how to solve this. The ball is |
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on their side. |
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> Well, if they considered the C++11 ABI in gcc-4.9 stable, we could |
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> consider changing the default to C++11. Then, we could do our |
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> bump/switch thing as a matter of gcc-4.9 upgrade problem. |
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To put things into perspective, *if* the ABI changes and if the new version |
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is compatible between C++98 and C++11, then we're talking something very |
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similar to an upgrade from GCC 3.3. |
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Cheers, |
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Jan |
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