Merge bitcoin/bitcoin#27029: guix: consolidate to glibc 2.27 for Linux builds

d5d4b75840b4219495ed0fc421a4b71e757224ee guix: combine glibc hardening options into hardened-glibc (fanquake)
c49f2b8eb5d70aea76e2aa06cdfcb2cc9fa1cb53 guix: remove no-longer needed powerpc workaround (fanquake)
74c989398971864afc7098818262ff0b76fbcf71 guix: use glibc 2.27 for all Linux builds (fanquake)

Pull request description:

  Build against glibc 2.27 for all Linux builds (previously only used for RISC-V), and at the same time, increase our minimum required glibc to 2.27 (2018). This would drop support for Ubuntu Xenial (16.04) & Debian Stretch (9), from the produced release binaries. Compiling from source on those systems may be possible, assuming you can install a recent enough compiler/toolchain etc.

ACKs for top commit:
  hebasto:
    ACK d5d4b75840b4219495ed0fc421a4b71e757224ee, I have reviewed the code and it looks OK, I agree it can be merged.

Tree-SHA512: 910f0ef45b4558f2a45d35a5c1c39aaac97e8aff086dc4fc1eddbb80c0b6e4bd23667d64e21d0fd42e4db37b6f26f447ca5d1150bb861128af7e71fb42835cf8

1 files changed, 0 insertions, 25 deletions

diff --git a/contrib/devtools/test-symbol-check.py b/contrib/devtools/test-symbol-check.py
index de73b02090..e304880140 100755
--- a/contrib/devtools/test-symbol-check.py
+++ b/contrib/devtools/test-symbol-check.py
@@ -38,31 +38,6 @@ class TestSymbolChecks(unittest.TestCase):
         executable = 'test1'
         cc = determine_wellknown_cmd('CC', 'gcc')
 
-        # there's no way to do this test for RISC-V at the moment; we build for
-        # RISC-V in a glibc 2.27 environment and we allow all symbols from 2.27.
-        if 'riscv' in get_machine(cc):
-            self.skipTest("test not available for RISC-V")
-
-        # nextup was introduced in GLIBC 2.24, so is newer than our supported
-        # glibc (2.18), and available in our release build environment (2.24).
-        with open(source, 'w', encoding="utf8") as f:
-            f.write('''
-                #define _GNU_SOURCE
-                #include <math.h>
-
-                double nextup(double x);
-
-                int main()
-                {
-                    nextup(3.14);
-                    return 0;
-                }
-        ''')
-
-        self.assertEqual(call_symbol_check(cc, source, executable, ['-lm']),
-                (1, executable + ': symbol nextup from unsupported version GLIBC_2.24(3)\n' +
-                    executable + ': failed IMPORTED_SYMBOLS'))
-
         # -lutil is part of the libc6 package so a safe bet that it's installed
         # it's also out of context enough that it's unlikely to ever become a real dependency
         source = 'test2.c'