On 09/02/21 22:05 +0100, François Dumont via Libstdc++ wrote:
libstdc++: Fix versioned namespace build
libstdc++-v3/ChangeLog:
* libsupc++/eh_ptr.cc (exception_ptr(__safe_bool)): Define if
_GLIBCXX_EH_PTR_COMPAT is defined.
(exception_ptr::_M_safe_bool_dummy()): Likewise.
(exception_ptr::operator!()): Likewise.
(exception_ptr::opeerator __safe_bool()): Likewise.
Ok to commit ?
No, this is not correct. Those functions are declared in the
header if included from C++98 code:
#if (__cplusplus < 201103L) || defined (_GLIBCXX_EH_PTR_COMPAT)
typedef void (exception_ptr::*__safe_bool)();
// For construction from nullptr or 0.
exception_ptr(__safe_bool) _GLIBCXX_USE_NOEXCEPT;
#endif
With your change, C++98 code that calls those functions will be unable
to link to libstdc++.so.8 because the functions won't be defined in
the library.
The simplest fix would be to revert this change:
--- a/libstdc++-v3/libsupc++/eh_ptr.cc
+++ b/libstdc++-v3/libsupc++/eh_ptr.cc
@@ -25,7 +25,12 @@
#include <bits/c++config.h>
#include "eh_atomics.h"
+#if ! _GLIBCXX_INLINE_VERSION
+// This macro causes exception_ptr to declare an older API (with corresponding
+// definitions in this file) and to mark some inline functions as "used" so
+// that definitions will be emitted in this translation unit.
#define _GLIBCXX_EH_PTR_COMPAT
+#endif
#include <exception>
#include <bits/exception_ptr.h>
But that leaves the unwanted operator== definitions in libstdc++.so.8
so the attached patch (only tested with unversioned namespace) is
probably what we want to do. Does it fix the problem?
diff --git a/libstdc++-v3/libsupc++/eh_ptr.cc b/libstdc++-v3/libsupc++/eh_ptr.cc
index 5d8ac1d879a..5c4685606fe 100644
--- a/libstdc++-v3/libsupc++/eh_ptr.cc
+++ b/libstdc++-v3/libsupc++/eh_ptr.cc
@@ -25,11 +25,15 @@
#include <bits/c++config.h>
#include "eh_atomics.h"
-#if ! _GLIBCXX_INLINE_VERSION
// This macro causes exception_ptr to declare an older API (with corresponding
-// definitions in this file) and to mark some inline functions as "used" so
-// that definitions will be emitted in this translation unit.
+// definitions in this file).
#define _GLIBCXX_EH_PTR_COMPAT
+
+#if ! _GLIBCXX_INLINE_VERSION
+// This macro causes some inline functions in exception_ptr to be marked
+// as "used" so that definitions will be emitted in this translation unit.
+// We need this because those functions were not inline in previous releases.
+#define _GLIBCXX_EH_PTR_RELOPS_COMPAT
#endif
#include <exception>
diff --git a/libstdc++-v3/libsupc++/exception_ptr.h b/libstdc++-v3/libsupc++/exception_ptr.h
index 6d41b34fabe..9943668d9b3 100644
--- a/libstdc++-v3/libsupc++/exception_ptr.h
+++ b/libstdc++-v3/libsupc++/exception_ptr.h
@@ -39,7 +39,7 @@
#include <typeinfo>
#include <new>
-#ifdef _GLIBCXX_EH_PTR_COMPAT
+#ifdef _GLIBCXX_EH_PTR_RELOPS_COMPAT
# define _GLIBCXX_EH_PTR_USED __attribute__((__used__))
#else
# define _GLIBCXX_EH_PTR_USED
@@ -153,7 +153,7 @@ namespace std
#endif
#if __cpp_impl_three_way_comparison >= 201907L \
- && ! defined _GLIBCXX_EH_PTR_COMPAT
+ && ! defined _GLIBCXX_EH_PTR_RELOPS_COMPAT
friend bool
operator==(const exception_ptr&, const exception_ptr&) noexcept = default;
#else
