This has been around since the original import of Qt
(38be0d13830efd2d98281c645c3a60afe05ffece), however there
are now only two instatnces of it left in the qt codebase,
and from what I can gather, it's unused.
plugin_no_soname was removed from Qt some time ago, see upstream commit
1d034244c261520d5e739534dc264c2500e02b5f. It was replaced with
plugin_with_soname, however that is currently only used (as of 5.15.x)
in the Android Clang mkspec.
This should mostly be a no-op, however it would seem to make more sense
that we pass through the XCODE_VERSION we now have in depends, rather
than leaving the version set to 4.3.
This contains a few hacks very specific to Qt's buildsystem. These can be
reverted once we split the build between native and target builds.
Qt's build contains a circular dependency when not using a system zlib.
By far the easiest fix is to switch to a system zlib, rather than Qt's own.
However, that confuses Qt's cross build which assumes that when using a system
zlib, it should also find a system (native) zlib for native tools. The build
breaks if that zlib is not present.
To solve this:
1. Always use a system zlib rather than the one provided by qt
2. Set force_bootstrap, which instructs the build tools to be built as though
we're cross-compiling (build != target)
3. For build tools, use qt's internal zlib so that a native zlib is not
required.
Step 3 means that if any zlib headers are found by the native build, it will
confuse Qt's internal zlib build. So we also need to make sure that the target
headers/libs aren't found. To do so, specify that our
cflags/cxxflags/cppflags/ldflags only apply for non-host builds.
tl;dr: Update to the newer stable toolchain and SDK for OSX without giving up
any backwards compatibility. We can move to clang 3.5 as a next step which
allows use to use libc++ and the 10.10 sdk, but we'll need to find a build that
works in gitian/travis first.
Switch to a new, better maintained fork of cctools:
https://github.com/tpoechtrager/cctools-port
I've forked this and will be working on it some as well:
https://github.com/theuni/cctools-port
This brings in:
cctools v862
ld64: v241.9
It also fixes 64bit builds, so there's no longer any need to use a 32bit clang.
Since clang is no longer tied to an old/crusty 32bit build, clang has been
upgraded to 3.3. Unfortunately, there's a bug in 3.4 that breaks builds. 3.5
works fine, but there are no binary builds compatible with precise, which is
currently used for gitian and travis. We could always build our own if
necessary.
After updating to stable clang/linker/cctools, it's possible to use a more
recent SDK. The current SDK (10.7) through the most recent 10.10 have all been
built/tested successfully, both with and without 10.6 compatibility. However,
10.10 requires clang 3.5.
SDKs >= 10.9 use libc++ rather than libstdc++. This is verified working as well.
Hennadii Stepanov