Bug#817926: glibc: Please build with "--without-fp" on powerpcspe to enable FPU emulation

[John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>]

Source: glibc
Version: 2.22-2
Severity: normal
User: debian-powerpc@lists.debian.org
Usertags: powerpcspe

Hello!

glibc currently fails to build from source on powerpcspe because the configure
script defaults to "--with-fp" even when building natively on powerpcspe (e500).

Although the glibc build system detects e500 through the non-availability of FPRs
in sysdeps/powerpc/preconfigure:

case "$machine" in
powerpc64*)
  base_machine=powerpc machine=powerpc/powerpc64
  ;;
powerpc*)
  # Check for e500.
  $CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null > conftest.i
  if grep -q __NO_FPRS__ conftest.i && ! grep -q _SOFT_FLOAT conftest.i; then
    base_machine=powerpc machine=powerpc/powerpc32/e500
  else
    base_machine=powerpc machine=powerpc/powerpc32
  fi
  rm -f conftest.i
  ;;
esac

it does not enable the FPU emulation code with the "--without-fp" switch which
results in the aforementioned FTBFS [1]. Enabling FPU emulation in glibc is
also a requirement to be able to build gcc-5 on powerpcspe since newer versions
of gcc have been modified to use the FPU emulation in glibc instead of their
own emulation code in libgcc [2].

Thanks,
Adrian

> [1] https://buildd.debian.org/status/fetch.php?pkg=glibc&arch=powerpcspe&ver=2.19-18&stamp=1429072945
> [2] https://patchwork.ozlabs.org/patch/405072/

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz@debian.org
`. `'   Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913