[Bug web/82686] Debian sid powerpc64-unknown-linux-gnu 4.13.0-1-powerpc64 bootstrap breaks in stage3 with unexpected requirement for bdw-gc

[kdevel at vogtner dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82686

--- Comment #9 from Stefan <kdevel at vogtner dot de> ---
(In reply to Jonathan Wakely from comment #7)
> (In reply to Dennis Clarke from comment #6)
> > Actually first thing I did was remove a few options from configure stage
> > such that I could at least get past this small bump in the road : 
> > 
> >     --enable-multiarch and --enable-multilib removed. 
> > 
> > 
> > Configure went fine and the bootstrap went past the previous gc bump and then
> 
> Which confirms you needed the 32-bit gc packages.

For years I am building each and every new GCC with languages

   ada,c,c++,fortran,go,java,objc,obj-c++

Okay, Java is gone so I compile GCC 7.3.0 with

   langs=ada,c,c++,fortran,go,objc,obj-c++
   [prefix]/configure --prefix=$inst \
      --enable-objc-gc \
      --enable-languages=$langs
   make bootstrap

Never had I to supply any binary libgc. Instead I moved the source dir of the
garbage collector into GCC's source directory:

   tar xfz $src/gc-7.1.tar.gz
   mv gc-7.1 gc

This no longer works since GCC 7. I get:

   checking for sched.h... yes
   checking whether the target supports thread-local storage... yes
   checking if the type of bitfields matters... yes
   checking for bdw garbage collector... checking for system boehm-gc...
configure: error: system bdw-gc required but not found
   make[1]: *** [configure-target-libobjc] Fehler 1
   make[1]: Leaving directory `/scratch/mockbuild1/bld-7.3.0/gcc-objdir'
   make: *** [all] Fehler 2

This is Linux x86_64 GNU/Linux (Centos 6.9). How do I prompt GCC to compile the
Boehm GC?