x11-libs/cairo-1.12.14 fails to compile using clang+lto

Submitted by cmuelle8

Assigned to Chris Wilson @ickle

Link to original bug (#63310)

Description

Created attachment 77662 cairo-1.12.12-make-ac-float-endianess-test-llvm-bitcode-save.patch

I've posted this to bugs.gentoo.org before:

https://bugs.gentoo.org/show_bug.cgi?id=464982

As requested there, I repost the patches here. There are two issues I encountered when compiling cairo with "clang -O4":

1. bitcode representation of object files makes float endianess test in configure break (see attached patch)
2. "automatic configuration" of pthreads does not work while explicitly --enable-pthread=yes to configure does

If "--enable-pthread=yes" configure option is not passed, the default is "auto" instead of "yes", which basically runs the first block of the following lines in cairo-1.12.12/build/configure.ac.pthread (around line 220)

    dnl Check if we can use libc's stubs in libcairo.
    dnl Only do this if the user hasn't explicitly enabled
    dnl pthreads, but is relying on automatic configuration.
    have_pthread="no"
    if test "x$enable_pthread" != "xyes"; then
        CAIRO_CHECK_PTHREAD(
            [pthread], [-D_REENTRANT], [],
            [libcairo_pthread_program],
            [have_pthread=yes],
            [])
    fi

    dnl Default to using the real pthreads for libcairo.
    if test "x$have_pthread" != "xyes"; then
        have_pthread="$have_real_pthread";
        pthread_CFLAGS="$real_pthread_CFLAGS";
        pthread_LIBS="$real_pthread_LIBS";
    fi

This automatic configuration apparently does not work if clang -O4 is used, even though libcairo_pthread_program seems to succeed.

Or in other words: using libc stubs as a pthread provider currently does not work if clang -O4 is in use, the automatically configured stubs make the compile quit with

libtool: link: clang -march=native -pipe -fomit-frame-pointer -O4 -finline-limit=1200 -march=native -pipe -fomit-frame-pointer -O4 -Wl,-O1 -Wl,--hash-style=gnu -Wl,--sort-common -Wl,-z -Wl,norelro -o .libs/cairo-analyse-trace cairo-analyse-trace.o cairo-error.o  -Wl,--as-needed ../util/cairo-script/.libs/libcairo-script-interpreter.so ../util/cairo-missing/.libs/libcairo-missing.a ./.libs/libcairoperf.a ../boilerplate/.libs/libcairoboilerplate.a /var/tmp/paludis/x11-libs-cairo-1.12.12-r1/work/cairo-1.12.12/src/.libs/libcairo.so ../src/.libs/libcairo.so -lpixman-1 -lfontconfig -lfreetype -lEGL -ldl -lpng15 -lxcb-shm -lxcb-render -lxcb -lXrender -lX11 -lXext -lz -lGL -lOpenVG -lrt -lm
/var/tmp/paludis/x11-libs-cairo-1.12.12-r1/work/cairo-1.12.12/src/.libs/libcairo.so: error: undefined reference to 'pthread_mutexattr_settype'
/var/tmp/paludis/x11-libs-cairo-1.12.12-r1/work/cairo-1.12.12/src/.libs/libcairo.so: error: undefined reference to 'pthread_mutexattr_init'
/var/tmp/paludis/x11-libs-cairo-1.12.12-r1/work/cairo-1.12.12/src/.libs/libcairo.so: error: undefined reference to 'pthread_mutexattr_destroy'
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[4]: *** [cairo-analyse-trace] Error 1
make[4]: Leaving directory `/var/tmp/paludis/x11-libs-cairo-1.12.12-r1/work/cairo-1.12.12/perf'
make[3]: Leaving directory `/var/tmp/paludis/x11-libs-cairo-1.12.12-r1/work/cairo-1.12.12/perf'
make[2]: Leaving directory `/var/tmp/paludis/x11-libs-cairo-1.12.12-r1/work/cairo-1.12.12/perf'
make[3]: *** [all-recursive] Error 1
make[2]: *** [all] Error 2
make[1]: Leaving directory `/var/tmp/paludis/x11-libs-cairo-1.12.12-r1/work/cairo-1.12.12'
make[1]: *** [all-recursive] Error 1
make: *** [all] Error 2

I'm unsure about a proper fix for this, but thought about patch configure.ac.pthread to use real_pthread as an automatic configuration i.e. throw out libc stubs, use real_pthread if libcairo_pthread_program

Thanks

Patch 77662, "cairo-1.12.12-make-ac-float-endianess-test-llvm-bitcode-save.patch":
cairo-1.12.12-make-ac-float-endianess-test-llvm-bitcode-save.patch

Version: 1.12.12

See also

• https://bugs.gentoo.org/show_bug.cgi?id=464982