[gcc r12-9454] libstdc++: Do not use facets cached in ios for ALT128 build [PR103387]

[Jonathan Wakely]

https://gcc.gnu.org/g:24cf9f4c6f45f7d8b37757cdb34576ee5d2d40e1

commit r12-9454-g24cf9f4c6f45f7d8b37757cdb34576ee5d2d40e1
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Tue Mar 28 21:07:21 2023 +0100

    libstdc++: Do not use facets cached in ios for ALT128 build [PR103387]
    
    For the powerpc64le build with two different long double
    representations, we cannot use the ios_base::_M_num_put and
    ios_base::_M_num_get pointers, because they might have been initialized
    in a translation unit using the other long double type. With the changes
    to add __try_use_facet to GCC 13 the cache isn't really needed now, we
    can just access the right facet in the locale directly, without needing
    RTTI checks.
    
    libstdc++-v3/ChangeLog:
    
            PR libstdc++/103387
            * include/bits/istream.tcc (istream::_M_extract(ValueT&)): Use
            std::use_facet instead of cached _M_num_get facet.
            (istream::operator>>(short&)): Likewise.
            (istream::operator>>(int&)): Likewise.
            * include/bits/ostream.tcc (ostream::_M_insert(ValueT)): Use
            std::use_facet instead of cached _M_num_put facet.
    
    (cherry picked from commit ec12639c82e944d37200a744156e183ea19add00)

Diff:
---
 libstdc++-v3/include/bits/istream.tcc | 15 +++++++++++++++
 libstdc++-v3/include/bits/ostream.tcc |  5 +++++
 2 files changed, 20 insertions(+)

diff --git a/libstdc++-v3/include/bits/istream.tcc b/libstdc++-v3/include/bits/istream.tcc
index a1a7d89335e..dc4be3461d4 100644
--- a/libstdc++-v3/include/bits/istream.tcc
+++ b/libstdc++-v3/include/bits/istream.tcc
@@ -102,7 +102,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	    ios_base::iostate __err = ios_base::goodbit;
 	    __try
 	      {
+#ifndef _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT
 		const __num_get_type& __ng = __check_facet(this->_M_num_get);
+#else
+		const __num_get_type& __ng
+		  = use_facet<__num_get_type>(this->_M_ios_locale);
+#endif
 		__ng.get(*this, 0, *this, __err, __v);
 	      }
 	    __catch(__cxxabiv1::__forced_unwind&)
@@ -132,7 +137,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  __try
 	    {
 	      long __l;
+#ifndef _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT
 	      const __num_get_type& __ng = __check_facet(this->_M_num_get);
+#else
+	      const __num_get_type& __ng
+		= use_facet<__num_get_type>(this->_M_ios_locale);
+#endif
 	      __ng.get(*this, 0, *this, __err, __l);
 
 	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
@@ -177,7 +187,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  __try
 	    {
 	      long __l;
+#ifndef _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT
 	      const __num_get_type& __ng = __check_facet(this->_M_num_get);
+#else
+	      const __num_get_type& __ng
+		= use_facet<__num_get_type>(this->_M_ios_locale);
+#endif
 	      __ng.get(*this, 0, *this, __err, __l);
 
 	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
diff --git a/libstdc++-v3/include/bits/ostream.tcc b/libstdc++-v3/include/bits/ostream.tcc
index ba337c81aa8..05e684275f5 100644
--- a/libstdc++-v3/include/bits/ostream.tcc
+++ b/libstdc++-v3/include/bits/ostream.tcc
@@ -69,7 +69,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	    ios_base::iostate __err = ios_base::goodbit;
 	    __try
 	      {
+#ifndef _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT
 		const __num_put_type& __np = __check_facet(this->_M_num_put);
+#else
+		const __num_put_type& __np
+		  = use_facet<__num_put_type>(this->_M_ios_locale);
+#endif
 		if (__np.put(*this, *this, this->fill(), __v).failed())
 		  __err |= ios_base::badbit;
 	      }