cc/gcc: add option to enable/disable decimal floats

Decimal floats need support form the C library, namely support
for fenv, which is missing in uClibc for any architecture but
x86/32.

Add an option (a choice) to enable or disable decimal floats.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

libc/eglibc: does no longer support LinuxThreads

LinuxThreads are dead. Buried 6 feet under. Long forgotten.
Time for mourning has to come to an end.

But fear not, younster, for we have a great successor as NPTL!
Times for rejoicing have come, now!

LinuxThreads are dead. Long live NPTL!

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

cc/gcc: bump Linaro versions

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

libc/uClibc: add option to enable fenv

Support for fenv.h is a little bit more tricky that enabling it only
for x86-32 is not right.

Add an option for the user to choose whther to install fenv.h or not.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

libc/glibc: fix downloading addons

Do to glibc what we did to eglibc in #dff359adf15c.

Only (very) old versions of glibc have other external addons,
and they are no longer meaningful.

But for consistency, do the change nonetheless.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

libc/glibc: print name of skipped addon

When trying to extract an already present (aka bundled) addon,
print the name of that addon, for clarity, and to help analyse
the build.log post-mortem.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

cc/gcc: set CXXFLAGS at configure gcc

Since gcc 4.8 C++ is also used as implementation language (see gcc
release notes).

Signed-off-by: "Daniel Dittmann" <ddittmann@gmx.net>
Message-Id: <acc7d11bc77b30f21c5b.1388863298@bernalk.machteam>
Patchwork-Id: 306883

libc-uclibc: enable fenv for x86 32-bit

Without it, gcc-4.8 fails to build.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

cc/gcc: diable libsanitizer without NPTL

gcc-4.8 comes with a new library to sanitise memory access:
- heap-, stack-, and global-buffer overflow, use-after-free
- data-races between threads

This library requires some _np parts of the API, which are not
implemented in the (old) LinuxThreads, which is still available
in uClibc.

Since NPTL requires a i486 or above, i386 are stuck with using LT,
which precludes building the libsanitizer.

Disable libsanitizer, a bit like libatomic is.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Niels Penneman <niels@penneman.org>

libc/eglibc: fix downloading of localedef addon

For the versions of eglibc where the ports addon is not external (ie,
all versions after, and including 2.17), we would fail to download the
localedef addon, since the test did not care about the addon we were
about to download, only whether the ports addon was external or not.

Fix that by skipping the ports addon only if that's the addon we're
trying to download.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>