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boostorg / container_hash

Generic hash function for STL style unordered containers
https://boost.org/libs/container_hash
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Removed usage of std::unary_function for C++17 compliance #6

Closed andrascii closed 5 years ago

andrascii commented 5 years ago

Just to be able to compile boost with projects that uses C++17.

mclow commented 5 years ago

The use of unary_function is already guarded by an #ifdef, removing it outright seems unnecessary. It seems to be that it would be better to fix the conditional.

mclow commented 5 years ago

from the Boost.Config docs:

BOOST_NO_CXX98_FUNCTION_BASE: The standard library no longer supports std::unary_function and std::binary_function. They were deprecated in C++11 and is removed from C++14.

jzmaddock commented 5 years ago

@mclow: this looks good to me now - corrects the PP logic as it should.

mclow commented 5 years ago

Do we need the _HAS_AUTO_PTR_ETC checks at all?

andrascii commented 5 years ago

Do we need the _HAS_AUTO_PTR_ETC checks at all?

Specifically in this part of code? If _HAS_AUTO_PTR_ETC is defined to 0, std::auto_ptr and std::random_shuffle are not available.

What does this _HAS_AUTO_PTR_ETC have to do with this code? It looks like this macro was used to understand that std::unary_function was removed...

jzmaddock commented 5 years ago

Do we need the _HAS_AUTO_PTR_ETC checks at all?

Probably not any more, they're msvc specific and have been superseded by BOOST_NO_CXX98_FUNCTION_BASE.

andrascii commented 5 years ago

This solutions isn't working. Compiler still has an error about std::unary_function. Macro BOOST_NO_CXX98_FUNCTION_BASE isn't defined when I building the project. I use cmake and set: set(CMAKE_CXX_STANDARD 17) And I use clang.

I still think that we need to just remove usage of std::unary_function.

Any suggestions?

jzmaddock commented 5 years ago

This solutions isn't working. Compiler still has an error about std::unary_function.

What's the clang version, platform and standard library? We do test this in the Boost.Config tests so it should all be working.

BTW it would be wrong to simply remove all references to std::unary_function as that potentially breaks existing code.

andrascii commented 5 years ago

This solutions isn't working. Compiler still has an error about std::unary_function.

What's the clang version, platform and standard library? We do test this in the Boost.Config tests so it should all be working.

BTW it would be wrong to simply remove all references to std::unary_function as that potentially breaks existing code.

clang version: Apple LLVM version 10.0.1 (clang-1001.0.46.4) Target: x86_64-apple-darwin18.7.0 Thread model: posix InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

Compile flag -std=gnu++1z also used

jzmaddock commented 5 years ago

Well this is weird:

So maybe this is an Apple thing?

So I guess the question is whether we should define BOOST_NO_CXX98_FUNCTION_BASE for any compiler claiming to be C++14 or later "just in case" ?

andrascii commented 5 years ago

So maybe this is an Apple thing?

Maybe it is. But current solution for me is to define BOOST_NO_CXX98_FUNCTION_BASE on my own before including boost/functional/hash.hpp or just to avoid including this library. Because standard library that is shipped with Xcode does not contain the std::unary_function definition.

mclow commented 5 years ago

Because standard library that is shipped with Xcode does not contain the std::unary_function definition.

This is very confusing to me. I don't have Xcode installed, but I do have the most recent Apple command-line tools installed, and the headers that ship with those Apple LLVM version 10.0.1 (clang-1001.0.46.4) definitely DO define unary_function on line 960 of <utility>.

andrascii commented 5 years ago

Because standard library that is shipped with Xcode does not contain the std::unary_function definition.

This is very confusing to me. I don't have Xcode installed, but I do have the most recent Apple command-line tools installed, and the headers that ship with those Apple LLVM version 10.0.1 (clang-1001.0.46.4) definitely DO define unary_function on line 960 of <utility>.

Okey, I'll recheck this thing today/tomorrow.

andrascii commented 5 years ago

This is very confusing to me. I don't have Xcode installed, but I do have the most recent Apple command-line tools installed, and the headers that ship with those Apple LLVM version 10.0.1 (clang-1001.0.46.4) definitely DO define unary_function on line 960 of <utility>.

I'm sorry, my mistake. I forgot to install patched library and regenerate my project using cmake.