failed to build on Ubuntu 18.04 with GDC

[biocyberman]

Installed gdc:

 gdc --version
gdc (Ubuntu 8-20180414-1ubuntu2) 8.0.1 20180414 (experimental) [trunk revision 259383]
...

Current commit:

git rev-parse HEAD   
baddc0a3fe97521e0b7fdbc1a45bde18afed4314

And then make failed on

make gdc  
git describe --tags > bin/githash.txt                                                                                                                                                                                                       
mkdir -p bin                                                                                                                                                                                                                                
gdc src/dcd/common/socket.d src/dcd/common/dcd_version.d src/dcd/common/constants.d src/dcd/common/messages.d src/dcd/common/constants2.d src/dcd/server/autocomplete/util.d src/dcd/server/autocomplete/symbols.d src/dcd/server/autocomplet
e/localuse.d src/dcd/server/autocomplete/doc.d src/dcd/server/autocomplete/package.d src/dcd/server/autocomplete/complete.d src/dcd/server/main.d src/dcd/server/server.d dsymbol/src/dsymbol/symbol.d dsymbol/src/dsymbol/type_lookup.d dsym
bol/src/dsymbol/conversion/second.d dsymbol/src/dsymbol/conversion/first.d dsymbol/src/dsymbol/conversion/package.d dsymbol/src/dsymbol/modulecache.d dsymbol/src/dsymbol/semantic.d dsymbol/src/dsymbol/import_.d dsymbol/src/dsymbol/deferr
ed.d dsymbol/src/dsymbol/scope_.d dsymbol/src/dsymbol/string_interning.d dsymbol/src/dsymbol/cache_entry.d dsymbol/src/dsymbol/builtin/symbols.d dsymbol/src/dsymbol/builtin/names.d dsymbol/src/dsymbol/tests.d stdx-allocator/source/stdx/a
llocator/gc_allocator.d stdx-allocator/source/stdx/allocator/building_blocks/bitmapped_block.d stdx-allocator/source/stdx/allocator/building_blocks/affix_allocator.d stdx-allocator/source/stdx/allocator/building_blocks/free_tree.d stdx-a
llocator/source/stdx/allocator/building_blocks/allocator_list.d stdx-allocator/source/stdx/allocator/building_blocks/region.d stdx-allocator/source/stdx/allocator/building_blocks/kernighan_ritchie.d stdx-allocator/source/stdx/allocator/b
uilding_blocks/fallback_allocator.d stdx-allocator/source/stdx/allocator/building_blocks/scoped_allocator.d stdx-allocator/source/stdx/allocator/building_blocks/stats_collector.d stdx-allocator/source/stdx/allocator/building_blocks/null_
allocator.d stdx-allocator/source/stdx/allocator/building_blocks/quantizer.d stdx-allocator/source/stdx/allocator/building_blocks/free_list.d stdx-allocator/source/stdx/allocator/building_blocks/package.d stdx-allocator/source/stdx/alloc
ator/building_blocks/segregator.d stdx-allocator/source/stdx/allocator/building_blocks/bucketizer.d stdx-allocator/source/stdx/allocator/internal.d stdx-allocator/source/stdx/allocator/showcase.d stdx-allocator/source/stdx/allocator/mmap
_allocator.d stdx-allocator/source/stdx/allocator/typed.d stdx-allocator/source/stdx/allocator/mallocator.d stdx-allocator/source/stdx/allocator/common.d stdx-allocator/source/stdx/allocator/package.d libdparse/src/dparse/ast.d libdparse
/src/dparse/entities.d libdparse/src/dparse/lexer.d libdparse/src/dparse/parser.d libdparse/src/dparse/formatter.d libdparse/src/dparse/rollback_allocator.d libdparse/src/dparse/stack_buffer.d libdparse/src/std/experimental/lexer.d conta
iners/src/containers/dynamicarray.d containers/src/containers/ttree.d containers/src/containers/unrolledlist.d containers/src/containers/openhashset.d containers/src/containers/hashset.d containers/src/containers/internal/hash.d containe
rs/src/containers/internal/node.d containers/src/containers/internal/storage_type.d containers/src/containers/internal/element_type.d containers/src/containers/internal/backwards.d containers/src/containers/slist.d msgpack-d/src/msgpack/
buffer.d msgpack-d/src/msgpack/streaming_unpacker.d msgpack-d/src/msgpack/value.d msgpack-d/src/msgpack/register.d msgpack-d/src/msgpack/packer.d msgpack-d/src/msgpack/unpacker.d msgpack-d/src/msgpack/attribute.d msgpack-d/src/msgpack/co
mmon.d msgpack-d/src/msgpack/package.d msgpack-d/src/msgpack/exception.d -Icontainers/src -Imsgpack-d/src -Ilibdparse/src -Idsymbol/src -Jbin -O3 -frelease -obin/dcd-server                                                                
stdx-allocator/source/stdx/allocator/internal.d:1315:19: error: module std.experimental.allocator.common import 'Ternary' not found                                                                                                         
     public import std.experimental.allocator.common : Ternary;                                                                                                                                                                             
                   ^
makefile:142: recipe for target 'gdcserver' failed                                                                                                                                                                                          
make: *** [gdcserver] Error 1   

[ghost]

Looks like there's an error here:

static if (__VERSION__ >= 2072)
{
    public import std.typecons : Ternary;
}
else
{
    public import std.experimental.allocator.common : Ternary;
}

What does __VERSION__ expand to with the GDC you use (and which DMDFE does it use) ?
It's probably too old i think.

[wilzbach]

Ternary isn't part of the latest gdc in Ubuntu. It's supposedly uses the 2.076 frontend, but I think Ian just forgot to cherry-pick a few things.
TL; DR: use gdc master or LDC or DMD.

[ghost]

Sorry but we cant do anything here if there's been an omission in GDC version of libphobos.

[biocyberman]

So it's rather a GDC bug, @ibuclaw ?

[ibuclaw]

It's not a compiler bug.

[ghost]

see #534 (comment). Maybe you forgot some change in phobos.

[ibuclaw]

Keeping the version string at 2068 was deliberate, as the compiler does not implement 2.076 - its only a fork that covers most features and bug fixes in 2.076 backported to C++. Though eventually a concession was made (D-Programming-GDC/gdc#740) - lets hope no one uses static foreach for version >= 2076.

[ibuclaw]

You could use __traits(compiles) here instead of checking the version.

[ghost]

Okay so this is clear now, no issue here. It's probably not worth changing the version check since the problem will disappear with newer GDC releases.

[biocyberman]

Okay so this is clear now, no issue here. It's probably not worth changing the version check since the problem will disappear with newer GDC releases.

That means "nofix", in this case I should try to get the new GDC release compile DCD with it if I want to use GDC (I could compile successfully with DMD and LDC)?

[ghost]

If you really want i can add the code to make the selection of the import more clever.

[biocyberman]

👍 Yes, please do it if you can manage.

[ghost]

Can you try this code ?

void main(){}

static if (is(typeof({ import std.typecons : Ternary; })))
{
    public import std.typecons : Ternary;
}
else static if (is(typeof({ import std.experimental.allocator.common : Ternary;})))
{
    public import std.experimental.allocator.common : Ternary;
}
else static assert(0, "Oops, dont know how to find Ternary");     

since it's in a deps it will be faster to make the final PR in DCD if it's verified to be ok.
It it compiles it means that we can fix this issue.

[ghost]

@biocyberman you can approve there : dlang-community/stdx-allocator#10, if the above code works

[biocyberman]

I do not have access to the PC at the moment. Will test and get back to you later. Thanks.

[biocyberman]

@bbasile The code works. Thanks.