fix Issue 10710 - phobos depends on versioned libcurl

[MartinNowak]

• create a libcurl_stub.so for linking
• set it's soname to libcurl.so so that phobos
  gets a DT_NEEDED libcurl.so entry
• the runtime linker will load libcurl.so and resolve
  all undefined references
• disable pragma(lib, "curl") because it doesn't work
  for archives anyways and additionally links against
  the real libcurl

Issue 10710

[jordisayol]

With dmd v2.064 beta3:

$ objdump -x linux/lib64/libphobos2.so | grep " curl" | awk '{print $NF}'
curl_easy_setopt@@CURL_GNUTLS_3
curl_slist_append@@CURL_GNUTLS_3
curl_slist_free_all@@CURL_GNUTLS_3
curl_global_cleanup@@CURL_GNUTLS_3
curl_easy_strerror@@CURL_GNUTLS_3
curl_easy_init@@CURL_GNUTLS_3
curl_easy_cleanup@@CURL_GNUTLS_3
curl_easy_duphandle@@CURL_GNUTLS_3
curl_easy_perform@@CURL_GNUTLS_3
curl_easy_pause@@CURL_GNUTLS_3
curl_global_init@@CURL_GNUTLS_3

Whit this pull request:

$ objdump -x libphobos2.so.0.64.0 | grep " curl" | awk '{print $NF}'
curl_easy_setopt
curl_global_cleanup
curl_easy_init
curl_slist_append
curl_easy_pause
curl_slist_free_all
curl_easy_duphandle
curl_easy_perform
curl_easy_cleanup
curl_global_init
curl_easy_strerror

This pull request removes curl "versioned symbols" fixing the problem!

The SONAME "libcurl.so" forces to install curl development packages to run programs compiled with dmd/phobos. It should be "libcurl.so.4".

[MartinNowak]

Thx and done.
This should also go into 2.064 @WalterBright.

[jordisayol]

Autotest fails on OSX.
"libcurl_stub.so" should be generated on Linux building process only.

[MartinNowak]

OK, did this on linux only.

[jordisayol]

I'm agree that this should be merged before 2.064 release. @WalterBright @andralex ...

[braddr]

Why? The current state is not a regression over any previous release, much less the most recent release. It's an improvement, no doubt, but we're in regression fixing mode, not general improvement mode.

[braddr]

To forestall an obvious objection, any release since curl was added as a dependency. If you go back to pre-curl, then ok, but that's a good ways back at this point.

[jordisayol]

It's no a regression because Linux shared libraries are present from dmd v2.063.2, so it cannot be a regression, but if this is not merged, phobos shared libraries will be not usable on Linux systems that are not based on Debian, like Fedora, Centos, Redhat, OpenSUSE, LinuxArch, etc.

[MartinNowak]

Why? The current state is not a regression over any previous release, much less the most recent release. It's an improvement, no doubt, but we're in regression fixing mode, not general improvement mode.

Well the shared libphobos2.so that we shipped with the last release is broken on many linux distributions.
We support link-time shared libraries since the last release (through -defaultlib=libphobos2.so) and this pull is necessary to fix the feature.

[MartinNowak]

Why? The current state is not a regression over any previous release, much less the most recent release. It's an improvement, no doubt, but we're in regression fixing mode, not general improvement mode.

I'd rather not waste another release cycle without a working libphobos2.so because this blocks important work (e.g. shared library support in dub). Also we're hardly getting any testing/feedback for this still optional feature (-defaultlib=libphobos2.so) if it's not usable.

[MartinNowak]

Why? The current state is not a regression over any previous release, much less the most recent release. It's an improvement, no doubt, but we're in regression fixing mode, not general improvement mode.

For this release I could build the Fedora and openSUSE package so that we don't ship another broken libphobos2.so.

[jordisayol]

Good! But please use the last commit on https://github.com/D-Programming-Language/installer/blob/master/linux/dmd_rpm.sh instead of any previous release.

[MartinNowak]

Good! But please use the last commit on https://github.com/D-Programming-Language/installer/blob/master/linux/dmd_rpm.sh instead of any previous release.

Can you please open a pull request which cherry-picks the 2.064 relevant installer changes.

[jordisayol]

All the changes are already committed. You only have to use it with a modified (libphobos) release zip file, and don't forget to put https://github.com/D-Programming-Language/installer/blob/master/linux/dmd-completion together with the zip file. If not, the resulting packages will not have command line auto completion.

[MartinNowak]

All the changes are already committed.

Yes, but they're on master. We should build the 2.064 release with the 2.064 tag of the installer repo.

[jordisayol]

Ah, ok, but I have no idea how to do it.

[jordisayol]

Anyway, you will create the rpm packages from a non 2.064 tag, isn't it?

[MartinNowak]

Anyway, you will create the rpm packages from a non 2.064 tag, isn't it?

No can do, it's not reproducible.
Can you please list which of those commits are strictly required?
dlang/installer@v2.064...master

[jordisayol]

Can wait:
dlang/installer@ad8343b

Better if included:
dlang/installer@fde637f

Should be included:
dlang/installer@b930c30
dlang/installer@cad2103
dlang/installer@f3f9f08

[MartinNowak]

Let's resurrect this, it fixes 2 issues until we have per distribution build scripts. #1772.