build: remove libstdc++ backwards-compat

Backwards-compatibility for libstdc++ is not limited to straightforward abi
changes. Symbol visibility also needs to be taken into consideration, and
that really can't be addressed simply.

Instead, just static-link libstdc++ for backwards-compat.

configure.ac

@@ -133,7 +133,7 @@ AC_ARG_ENABLE([lcov],
 
 AC_ARG_ENABLE([glibc-back-compat],
   [AS_HELP_STRING([--enable-glibc-back-compat],
-  [enable backwards compatibility with glibc and libstdc++])],
+  [enable backwards compatibility with glibc])],
   [use_glibc_compat=$enableval],
   [use_glibc_compat=no])
 

src/Makefile.am

@@ -280,7 +280,6 @@ libbitcoin_util_a_SOURCES = \
 
 if GLIBC_BACK_COMPAT
 libbitcoin_util_a_SOURCES += compat/glibc_compat.cpp
-libbitcoin_util_a_SOURCES += compat/glibcxx_compat.cpp
 endif
 
 # cli: shared between bitcoin-cli and bitcoin-qt
@@ -372,7 +371,6 @@ libbitcoinconsensus_la_SOURCES = \
 
 if GLIBC_BACK_COMPAT
   libbitcoinconsensus_la_SOURCES += compat/glibc_compat.cpp
-  libbitcoinconsensus_la_SOURCES += compat/glibcxx_compat.cpp
 endif
 
 libbitcoinconsensus_la_LDFLAGS = -no-undefined $(RELDFLAGS)

src/compat/glibcxx_compat.cpp

@@ -1,94 +0,0 @@
-// Copyright (c) 2009-2014 The Bitcoin Core developers
-// Distributed under the MIT software license, see the accompanying
-// file COPYING or http://www.opensource.org/licenses/mit-license.php.
-
-#include <cstddef>
-#include <istream>
-#include <stdexcept>
-#include <typeinfo>
-
-#ifndef _GLIBCXX_USE_NOEXCEPT
-#define _GLIBCXX_USE_NOEXCEPT throw()
-#endif
-
-namespace std
-{
-const char* bad_exception::what() const throw()
-{
-    return "std::bad_exception";
-}
-
-const char* bad_cast::what() const throw()
-{
-    return "std::bad_cast";
-}
-
-const char* bad_alloc::what() const throw()
-{
-    return "std::bad_alloc";
-}
-
-namespace __detail
-{
-struct _List_node_base {
-    void _M_hook(std::__detail::_List_node_base* const __position) throw() __attribute__((used))
-    {
-        _M_next = __position;
-        _M_prev = __position->_M_prev;
-        __position->_M_prev->_M_next = this;
-        __position->_M_prev = this;
-    }
-
-    void _M_unhook() __attribute__((used))
-    {
-        _List_node_base* const __next_node = _M_next;
-        _List_node_base* const __prev_node = _M_prev;
-        __prev_node->_M_next = __next_node;
-        __next_node->_M_prev = __prev_node;
-    }
-
-    _List_node_base* _M_next;
-    _List_node_base* _M_prev;
-};
-} // namespace detail
-
-template ostream& ostream::_M_insert(bool);
-template ostream& ostream::_M_insert(long);
-template ostream& ostream::_M_insert(double);
-template ostream& ostream::_M_insert(unsigned long);
-template ostream& ostream::_M_insert(const void*);
-template ostream& __ostream_insert(ostream&, const char*, streamsize);
-template istream& istream::_M_extract(long&);
-template istream& istream::_M_extract(unsigned short&);
-
-out_of_range::~out_of_range() _GLIBCXX_USE_NOEXCEPT {}
-
-length_error::~length_error() _GLIBCXX_USE_NOEXCEPT {}
-
-// Used with permission.
-// See: https://github.com/madlib/madlib/commit/c3db418c0d34d6813608f2137fef1012ce03043d
-
-void ctype<char>::_M_widen_init() const
-{
-    char __tmp[sizeof(_M_widen)];
-    for (unsigned __i = 0; __i < sizeof(_M_widen); ++__i)
-        __tmp[__i] = __i;
-    do_widen(__tmp, __tmp + sizeof(__tmp), _M_widen);
-
-    _M_widen_ok = 1;
-    // Set _M_widen_ok to 2 if memcpy can't be used.
-    for (unsigned __i = 0; __i < sizeof(_M_widen); ++__i)
-        if (__tmp[__i] != _M_widen[__i]) {
-            _M_widen_ok = 2;
-            break;
-        }
-}
-
-void __throw_out_of_range_fmt(const char*, ...) __attribute__((__noreturn__));
-void __throw_out_of_range_fmt(const char* err, ...)
-{
-    // Safe and over-simplified version. Ignore the format and print it as-is.
-    __throw_out_of_range(err);
-}
-
-} // namespace std