[Boost-users] [atomic count] boost on apple gcc 4.2

Well, first, I think you prolly ought to be posting to the developers' list, and second I think you need a tag in the subject like "atomic count" so that the right people will look at it :-) on Thu Jul 31 2008, "Mat Marcus" wrote:

On Mon, Apr 28, 2008 at 3:22 PM, Peter Dimov wrote:

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Daniel Oberhoff:

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Hi,

Has anyone successfully used boost with the "new" apple gcc 4.2? I would like to since gcc42 has openmp, but I cant seem to be able to use boost. I compiled and installed boost with apple gcc 4.2 by directly using bjam with --toolset=darwin-4.2. When I try to use it I get an error (detailed output of gcc below) which hints towards problems with inline assembly. Actually, to get it compiled at all I had to set -fasm-blocks. Am I missing a flag of sorts? Or is it "just" another woe with apple's modified assembler?

Is the new Apple GCC documented somewhere? I wasn't able to find anything related to a new assembler syntax or -fasm-blocks. Can you ask Apple to explain the issue? Stock g++ 4.2.x compiles the code, so the problem must be Apple-specific.

Ok, I've got a little bit more information on the Apple gcc 4.2 situation. Here is a snippet from an email dialog between a user and an apple compiler engineer:

user appears below with with prefix ">>" apple compiler engineer appears below with with prefix ">"

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Thank you very much for the detailed reply. Based on your information I deduce:

1) Using gcc 4.2 with 4.0 (c++) libraries is a supported configuration by Apple

Right.

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I then conclude that the C++ ABI is fully compatible between 4.0 and 4.2

Right.

[snip, then user hypothesizes as to why there are problems with boost under gcc 4.2/libstdc++ 4.0 on current Apple systems]

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This is the case because boost assumes that a 4.2 compiler implies 4.2 libraries in flies such as boost/detail/atomic_count_gcc.hpp:

#if (__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 2)) # include #else # include #endif

Yes, this is a bug or faulty assumption in boost.

[snip]

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The 4.2 library issue is a bug in Boost, not a problem with our compiler. I'd suggest raising the issue on one of the boost mailing lists and see what they say.

Comments? Mat _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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