package/glibc: switch to using the maintenance branch

glibc upstream has ruled against doing regular point-releases, but they
do have a lot of interesting and important fixes for regressions and
security.

Backporting each patch, or cherry-picking individual patches is off
limits for us, so we just switch to using the currently-latest HEAD of
the maintenance branch instead.

The version number is obtained with:
    $ git describe --match 'glibc-*' --abbrev=40 origin/release/2.26/master

The alternative options were:
  - download the tarball from the git tree
    --> does not work; not an option
  - download the 2.26 tarball, and bundle the individual patches in
    Buildroot
    --> maintenance of patches is a burden; not an option
  - download the 2.26 tarball, maintain the list of patches to download from
    the git tree
    --> not an option for the same reason

So we end up just doing a git clone. The git tree is today about ten
times the size of the tarball, so a rough estimate makes it at about ten
times the download time.

Also upstream doesn't officially provide an https download location [1].
There is one but it's not reliable, sometimes the connection time out and
end-up with a corrupted git repo:

fatal: unable to access 'https://sourceware.org/git/glibc.git/': Failed to connect to sourceware.org port 443: Connection timed out

So switch to using a git mirror from github which is updated once a day [2].
This allow at the same time to clone the git repository faster.

Note: The glibc 2.26 patches are not kept for the arc toolchain since they
are fixing an issue with the new float128 support introduced in x86, x86_64
and powerpc64le.

[1] https://sourceware.org/git/?p=glibc.git;a=summary
[2] https://github.com/bminor/glibc.git

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Romain Naour <romain.naour@openwide.fr>
Cc: Peter Korsgaard <peter@korsgaard.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Arnout Vandecappelle <arnout@mind.be>
Cc: Evgeniy Didin <didin@synopsys.com>
CC: Alexey Brodkin <abrodkin@synopsys.com>
[Romain: bump 4b692dffb95ac4812b161eb6a16113d7e824982e]
Signed-off-by: Romain Naour <romain.naour@gmail.com>
[yann.morin.1998@free.fr: update comment to never decide on the mirror]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Reviewed-by: Romain Naour <romain.naour@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

1 files changed, 0 insertions, 225 deletions

diff --git a/package/glibc/0003-Provide-a-C-version-of-issignaling-that-does-not-use.patch b/package/glibc/0003-Provide-a-C-version-of-issignaling-that-does-not-use.patch
deleted file mode 100644
index b9cd3df396..0000000000
--- a/package/glibc/0003-Provide-a-C-version-of-issignaling-that-does-not-use.patch
+++ /dev/null
@@ -1,225 +0,0 @@
-From 9bcf391a21677c6d5fa1c2be71554ec181e24f39 Mon Sep 17 00:00:00 2001
-From: "Gabriel F. T. Gomes" <gftg@linux.vnet.ibm.com>
-Date: Mon, 14 Aug 2017 13:46:15 -0300
-Subject: [PATCH] Provide a C++ version of issignaling that does not use
- __MATH_TG
-
-The macro __MATH_TG contains the logic to select between long double and
-_Float128, when these types are ABI-distinct.  This logic relies on
-__builtin_types_compatible_p, which is not available in C++ mode.
-
-On the other hand, C++ function overloading provides the means to
-distinguish between the floating-point types.  The overloading
-resolution will match the correct parameter regardless of type
-qualifiers, i.e.: const and volatile.
-
-Tested for powerpc64le, s390x, and x86_64.
-
-	* math/math.h [defined __cplusplus] (issignaling): Provide a C++
-	definition for issignaling that does not rely on __MATH_TG,
-	since __MATH_TG uses __builtin_types_compatible_p, which is only
-	available in C mode.
-	(CFLAGS-test-math-issignaling.cc): New variable.
-	* math/Makefile [CXX] (tests): Add test-math-issignaling.
-	* math/test-math-issignaling.cc: New test for C++ implementation
-	of type-generic issignaling.
-	* sysdeps/powerpc/powerpc64le/Makefile [subdir == math]
-	(CXXFLAGS-test-math-issignaling.cc): Add -mfloat128 to the build
-	options of test-math-issignaling on powerpc64le.
-
-(cherry picked from commit a16e8bc08edca84d507715c66d6cddbbc7ed3b62)
-[Romain rebase on glibc 2.26]
-Signed-off-by: Romain Naour <romain.naour@gmail.com>
----
- math/Makefile                        |   3 +-
- math/math.h                          |  19 +++++-
- math/test-math-issignaling.cc        | 113 +++++++++++++++++++++++++++++++++++
- sysdeps/powerpc/powerpc64le/Makefile |   1 +
- 4 files changed, 134 insertions(+), 2 deletions(-)
- create mode 100644 math/test-math-issignaling.cc
-
-diff --git a/math/Makefile b/math/Makefile
-index e09b0c0..0130fcf 100644
---- a/math/Makefile
-+++ b/math/Makefile
-@@ -203,7 +203,7 @@ tests-static = test-fpucw-static test-fpucw-ieee-static \
- 	       test-signgam-ullong-static test-signgam-ullong-init-static
- 
- ifneq (,$(CXX))
--tests += test-math-isinff test-math-iszero
-+tests += test-math-isinff test-math-iszero test-math-issignaling
- endif
- 
- ifneq (no,$(PERL))
-@@ -350,6 +350,7 @@ CFLAGS-test-signgam-ullong-init-static.c = -std=c99
- 
- CFLAGS-test-math-isinff.cc = -std=gnu++11
- CFLAGS-test-math-iszero.cc = -std=gnu++11
-+CFLAGS-test-math-issignaling.cc = -std=gnu++11
- 
- CFLAGS-test-iszero-excess-precision.c = -fexcess-precision=standard
- CFLAGS-test-iseqsig-excess-precision.c = -fexcess-precision=standard
-diff --git a/math/math.h b/math/math.h
-index dea8dbe..add86af 100644
---- a/math/math.h
-+++ b/math/math.h
-@@ -474,7 +474,24 @@ enum
- # include <bits/iscanonical.h>
- 
- /* Return nonzero value if X is a signaling NaN.  */
--# define issignaling(x) __MATH_TG ((x), __issignaling, (x))
-+# ifndef __cplusplus
-+#  define issignaling(x) __MATH_TG ((x), __issignaling, (x))
-+# else
-+   /* In C++ mode, __MATH_TG cannot be used, because it relies on
-+      __builtin_types_compatible_p, which is a C-only builtin.  On the
-+      other hand, overloading provides the means to distinguish between
-+      the floating-point types.  The overloading resolution will match
-+      the correct parameter (regardless of type qualifiers (i.e.: const
-+      and volatile).  */
-+extern "C++" {
-+inline int issignaling (float __val) { return __issignalingf (__val); }
-+inline int issignaling (double __val) { return __issignaling (__val); }
-+inline int issignaling (long double __val) { return __issignalingl (__val); }
-+#  if __HAVE_DISTINCT_FLOAT128
-+inline int issignaling (_Float128 __val) { return __issignalingf128 (__val); }
-+#  endif
-+} /* extern C++ */
-+# endif
- 
- /* Return nonzero value if X is subnormal.  */
- # define issubnormal(x) (fpclassify (x) == FP_SUBNORMAL)
-diff --git a/math/test-math-issignaling.cc b/math/test-math-issignaling.cc
-new file mode 100644
-index 0000000..22ae9e1
---- /dev/null
-+++ b/math/test-math-issignaling.cc
-@@ -0,0 +1,113 @@
-+/* Test for the C++ implementation of issignaling.
-+   Copyright (C) 2017 Free Software Foundation, Inc.
-+   This file is part of the GNU C Library.
-+
-+   The GNU C Library is free software; you can redistribute it and/or
-+   modify it under the terms of the GNU Lesser General Public
-+   License as published by the Free Software Foundation; either
-+   version 2.1 of the License, or (at your option) any later version.
-+
-+   The GNU C Library is distributed in the hope that it will be useful,
-+   but WITHOUT ANY WARRANTY; without even the implied warranty of
-+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-+   Lesser General Public License for more details.
-+
-+   You should have received a copy of the GNU Lesser General Public
-+   License along with the GNU C Library; if not, see
-+   <http://www.gnu.org/licenses/>.  */
-+
-+#define _GNU_SOURCE 1
-+#include <math.h>
-+#include <stdio.h>
-+
-+#include <limits>
-+
-+/* There is no signaling_NaN for _Float128 in std::numeric_limits.
-+   Include ieee754_float128.h and use the bitfields in the union
-+   ieee854_float128.ieee_nan to build a signaling NaN.  */
-+#if __HAVE_DISTINCT_FLOAT128
-+# include <ieee754_float128.h>
-+#endif
-+
-+static bool errors;
-+
-+static void
-+check (int actual, int expected, const char *actual_expr, int line)
-+{
-+  if (actual != expected)
-+    {
-+      errors = true;
-+      printf ("%s:%d: error: %s\n", __FILE__, line, actual_expr);
-+      printf ("%s:%d:   expected: %d\n", __FILE__, line, expected);
-+      printf ("%s:%d:   actual: %d\n", __FILE__, line, actual);
-+    }
-+}
-+
-+#define CHECK(actual, expected) \
-+  check ((actual), (expected), #actual, __LINE__)
-+
-+template <class T>
-+static void
-+check_type ()
-+{
-+  typedef std::numeric_limits<T> limits;
-+  CHECK (issignaling (T{0}), 0);
-+  if (limits::has_infinity)
-+    {
-+      CHECK (issignaling (limits::infinity ()), 0);
-+      CHECK (issignaling (-limits::infinity ()), 0);
-+    }
-+  if (limits::has_quiet_NaN)
-+    CHECK (issignaling (limits::quiet_NaN ()), 0);
-+  if (limits::has_signaling_NaN)
-+    CHECK (issignaling (limits::signaling_NaN ()), 1);
-+}
-+
-+#if __HAVE_DISTINCT_FLOAT128
-+static void
-+check_float128 ()
-+{
-+  ieee854_float128 q;
-+
-+  q.d = 0;
-+  CHECK (issignaling (q.d), 0);
-+
-+  /* Infinity.  */
-+  q.ieee.negative = 0;
-+  q.ieee.exponent = 0x7FFF;
-+  q.ieee.mantissa0 = 0x0000;
-+  q.ieee.mantissa1 = 0x00000000;
-+  q.ieee.mantissa2 = 0x00000000;
-+  q.ieee.mantissa3 = 0x00000000;
-+  CHECK (issignaling (q.d), 0);
-+
-+  /* Quiet NaN.  */
-+  q.ieee_nan.quiet_nan = 1;
-+  q.ieee_nan.mantissa0 = 0x0000;
-+  CHECK (issignaling (q.d), 0);
-+
-+  /* Still a quiet NaN.  */
-+  q.ieee_nan.quiet_nan = 1;
-+  q.ieee_nan.mantissa0 = 0x4000;
-+  CHECK (issignaling (q.d), 0);
-+
-+  /* Signaling NaN.  */
-+  q.ieee_nan.quiet_nan = 0;
-+  q.ieee_nan.mantissa0 = 0x4000;
-+  CHECK (issignaling (q.d), 1);
-+}
-+#endif
-+
-+static int
-+do_test (void)
-+{
-+  check_type<float> ();
-+  check_type<double> ();
-+  check_type<long double> ();
-+#if __HAVE_DISTINCT_FLOAT128
-+  check_float128 ();
-+#endif
-+  return errors;
-+}
-+
-+#include <support/test-driver.c>
-diff --git a/sysdeps/powerpc/powerpc64le/Makefile b/sysdeps/powerpc/powerpc64le/Makefile
-index 77617b6..19adbfa 100644
---- a/sysdeps/powerpc/powerpc64le/Makefile
-+++ b/sysdeps/powerpc/powerpc64le/Makefile
-@@ -16,6 +16,7 @@ $(foreach suf,$(all-object-suffixes),%f128_r$(suf)): CFLAGS += -mfloat128
- $(foreach suf,$(all-object-suffixes),$(objpfx)test-float128%$(suf)): CFLAGS += -mfloat128
- $(foreach suf,$(all-object-suffixes),$(objpfx)test-ifloat128%$(suf)): CFLAGS += -mfloat128
- CFLAGS-libm-test-support-float128.c += -mfloat128
-+CFLAGS-test-math-issignaling.cc += -mfloat128
- $(objpfx)test-float128% $(objpfx)test-ifloat128%: \
-   gnulib-tests += $(f128-loader-link)
- endif
--- 
-2.9.5
-