Re: [boost] [type_traits] Rewrite and dependency free version

On 1/15/2015 3:58 AM, John Maddock wrote:

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Testing gcc on Windows 7 with mingw and mingw64:

Running type_traits tests passed with msvc-8.0, msvc-9.0, gcc-4.4.0, gcc-4.5.0, gcc-4.5.2, and gcc-4.9.2.

Failed with gcc-4.3.0 with:

"testing.capture-output ..\..\..\bin.v2\libs\type_traits\test\has_nothrow_assign_test.test\gcc-mingw-4.3.0\debug\has_nothrow_assign_test.run

====== BEGIN OUTPUT ====== has_nothrow_assign_test.cpp:204: The expression: "::boost::has_nothrow_assign::value" had an invalid value (found 1, expected 0)"

I assume the current version has the same failure?

You are correct. There is no difference between the current version and Version2.

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In type_traits with gcc versions below 4 there are lots of failures of the order of:

"gcc.compile.c++ ..\..\..\bin.v2\libs\type_traits\test\is_virtual_base_of_test.test\gcc-mingw-3.4.5\debug\is_virtual_base_of_test.o

../../../boost/type_traits/is_virtual_base_of.hpp: In instantiation of `boost::detail::is_virtual_base_of_impl

...

::boost_type_traits_internal_struct_X': ../../../boost/type_traits/is_virtual_base_of.hpp:65: instantiated from `boost::detail::is_virtual_base_of_impl >' ../../../boost/type_traits/is_virtual_base_of.hpp:73: instantiated from `boost::detail::is_virtual_base_of_impl2' ../../../boost/type_traits/is_virtual_base_of.hpp:82: instantiated from `boost::is_virtual_base_of'"

etc. Of course I can't imagine anyone still using those versions.

You missed out the error message!

Just warnings and no error message.

But again, does the current version have the same failure?

The current version has similar failures. I don't see an error message with the failures in either the current version or the version2 version for gcc-3.4.5, just lots of warnings with "...failed gcc.compile.c++ ... " messages. Are the type_traits tests set to fail if any warnings occur ? It hardly seems necessary for type_traits to support gcc-3. I shouldn't have bothered testing it anyway.

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The function_types library depends on some type_traits implementation which is not in Version2, and tti uses function_types etc so tti fails.

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* If anyone would like to help converting further traits all help would be much appreciated.... Oh and the compiler requirements in the docs are all wildly out of date too...

Where are the compiler requirements for type_traits mentioned ?

There are out of date mentions in the docs - it all needs a *lot* of revising.

I could not find any mention of compiler requirements in the type_traits docs, much less out of date mentions, other than in the topic "Support for Compiler Intrinsics".

If you mean "what are the requirements for this rewrite", then I don't know yet... *should* be the same as the current code modulo the usual SNAFU's