Re: [gentoo-alt] [PREFIX] bootstrap status

[Michael Weiser]

Hello Fabian,

On Tue, Jan 09, 2018 at 04:58:56PM +0100, Fabian Groffen wrote:

> During the small break at the end of last year and beginning of this
> year, I've managed to get bootstrapping on Prefix running again.  In
> particular, thanks Michael Weiser for his continued support for macOS.

Thanks for *your* time! At one point it positively felt like playing
bugzilla ping-pong getting things done.

> I've myself successfully bootstrapped:
> - x64-macos on macOS High Sierra (Sierra to be tested)

I had a bootstrap succeed without problems on Yosemite as well.

> bootstrap path wasn't maintained for a while, and I'm currently trying
> to figure out how to continue from a llvm-4.3.2/libcxx-3.5.1 environment
> to get at least a proper functioning c++ environment.  This is fun(tm).

I tried this on both 10.5 and 10.6 Intel and ran into various problems.
Due to lack of an actual use-case I broke it off when these popped up:

10.5: llvm-3.4.2-r100 sanitizers failed to compile with:

/Users/michael/Gentoo/tmp/var/tmp/portage/sys-devel/llvm-3.4.2-r100/work/llvm-3.4.2.src/projects/compiler-rt/lib/sanitizer_common/sanitizer_p
latform_limits_posix.cc:839:1: error: 
      'assertion_failed__839' declared as an array with a negative size
CHECK_SIZE_AND_OFFSET(dirent, d_ino);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

It think last time around we just disabled the sanitizers.

10.6: clang/llvm/libcxx's insistance on compiling themselves 32/64bit
universal showcased again that our crt1.o's aren't:

    : && /Users/michael/Gentoo/tmp/bin/x86_64-apple-darwin10-clang++
-O2 -pipe -std=c++11 -stdlib=libc++
-I/Users/michael/Gentoo/usr/include/c++1/v1
-I/Users/michael/Gentoo/tmp/usr/include/c++1/v1 -arch i386 -arch x86_64
^^^ BTW: hack via CXXFLAGS to get libc++'s headers found

-std=c++11 -Wl,-search_paths_first -Wl,-headerpad_max_install_names
-stdlib=libc++ -L/Users/michael/Gentoo/usr/lib
-L/Users/michael/Gentoo/tmp/usr/lib
CMakeFiles/cmTC_a21b4.dir/testCXXCompiler.cxx.o  -o cmTC_a21b4   && :
    ld: warning: ignoring file
/Users/michael/Gentoo/usr/lib/crt1.10.6.o, file was built for
unsupported file format ( 0xCF 0xFA 0xED 0xFE 0x07 0x00 0x00 0x01 0x03
0x00 0x00 0x00 0x01 0x00 0x00 0x00 ) which is not the architecture being
linked (i386): /Users/michael/Gentoo/usr/lib/crt1.10.6.o
    Undefined symbols for architecture i386:
      "start", referenced from:
         implicit entry/start for main executable
    ld: symbol(s) not found for architecture i386
    clang: error: linker command failed with exit code 1 (use -v to see
invocation)
    ninja: build stopped: subcommand failed.

So we'd either need fat crt1.o's or compile the toolchain slim (which
would also speed up the build I expect).

IIRC crt1.o isn't used anymore from 10.7 onwards so this problem should
be moot for later systems.
-- 
Michael