PR libstdc++/51333 Define recursive_init_error constructor non-inline

The recursive_init_error class is defined in a header, with an inline
constructor, but the definition of the vtable and destructor are not
exported from the shared library. With -fkeep-inline-functions the
constructor gets emitted in user code, and requires the (non-exported)
vtable. This fails to link.

As far as I can tell, the recursive_init_error class definition was
moved into <cxxabi.h> so it could be documented with Doxygen, not for
any technical reason. But now it's there (and documented), somebody
could be relying on it, by catching that type and possibly performing
derived-to-base conversions to the std::exception base class. So the
conservative fix is to leave the class definition in the header but make
the constructor non-inline. This still allows the type to be caught and
still defines its base class.

Backport from mainline
2019-07-29  Jonathan Wakely  <jwakely@redhat.com>

	PR libstdc++/51333
	* libsupc++/cxxabi.h (__gnu_cxx::recursive_init_error): Do not define
	constructor inline.
	* libsupc++/guard_error.cc (__gnu_cxx::recursive_init_error): Define
	constructor.
	* testsuite/18_support/51333.cc: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-7-branch@275309 138bc75d-0d04-0410-961f-82ee72b054a4

4 files changed, 41 insertions, 6 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 732c70f289a..5ea3acf1f0a 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,6 +1,18 @@
 2019-09-02  Jonathan Wakely  <jwakely@redhat.com>
 
 	Backport from mainline
+	2019-07-29  Jonathan Wakely  <jwakely@redhat.com>
+
+	PR libstdc++/51333
+	* libsupc++/cxxabi.h (__gnu_cxx::recursive_init_error): Do not define
+	constructor inline.
+	* libsupc++/guard_error.cc (__gnu_cxx::recursive_init_error): Define
+	constructor.
+	* testsuite/18_support/51333.cc: New test.
+
+2019-09-02  Jonathan Wakely  <jwakely@redhat.com>
+
+	Backport from mainline
 	2019-06-07  Jonathan Wakely  <jwakely@redhat.com>
 
 	PR libstdc++/90770
diff --git a/libstdc++-v3/libsupc++/cxxabi.h b/libstdc++-v3/libsupc++/cxxabi.h
index 6e6b21ddbde..c4a400289a2 100644
--- a/libstdc++-v3/libsupc++/cxxabi.h
+++ b/libstdc++-v3/libsupc++/cxxabi.h
@@ -683,8 +683,9 @@ namespace __gnu_cxx
    *  @brief Exception thrown by __cxa_guard_acquire.
    *  @ingroup exceptions
    *
-   *  6.7[stmt.dcl]/4: If control re-enters the declaration (recursively)
-   *  while the object is being initialized, the behavior is undefined.
+   *  C++ 2011 6.7 [stmt.dcl]/4: If control re-enters the declaration
+   *  recursively while the variable is being initialized, the behavior
+   *  is undefined.
    *
    *  Since we already have a library function to handle locking, we might
    *  as well check for this situation and throw an exception.
@@ -694,8 +695,8 @@ namespace __gnu_cxx
   class recursive_init_error: public std::exception
   {
   public:
-    recursive_init_error() throw() { }
-    virtual ~recursive_init_error() throw ();
+    recursive_init_error() _GLIBCXX_NOTHROW;
+    virtual ~recursive_init_error() _GLIBCXX_NOTHROW;
   };
 }
 #endif // __cplusplus
diff --git a/libstdc++-v3/libsupc++/guard_error.cc b/libstdc++-v3/libsupc++/guard_error.cc
index 89b489459e7..cb3aad301a2 100644
--- a/libstdc++-v3/libsupc++/guard_error.cc
+++ b/libstdc++-v3/libsupc++/guard_error.cc
@@ -26,6 +26,6 @@
 
 namespace __gnu_cxx
 {
-  recursive_init_error::~recursive_init_error() throw() { }
+  recursive_init_error::recursive_init_error() noexcept { }
+  recursive_init_error::~recursive_init_error() noexcept { }
 }
-
diff --git a/libstdc++-v3/testsuite/18_support/51333.cc b/libstdc++-v3/testsuite/18_support/51333.cc
new file mode 100644
index 00000000000..0fb7c338f8b
--- /dev/null
+++ b/libstdc++-v3/testsuite/18_support/51333.cc
@@ -0,0 +1,22 @@
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This 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 General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-fkeep-inline-functions" }
+// { dg-do link }
+
+#include <cxxabi.h>
+int main() { } // PR libstdc++/51333