C++ code is not able to catch std::bad_cast exceptions, even though it should. If a dynamic_cast is within a try-catch block, then that block fails to catch std::bad_cast, and the program crashes with an uncaught exception as a result. I've attached a reproducible test case. You can also find it at http://forums.freebsd.org/showthread.php?p=205804#post205804 and http://stackoverflow.com/questions/14413703/why-does-catching-stdbad-cast-not-work-on-freebsd-9. The code is compiled with the following GCC version: $ gcc -v Using built-in specs. Target: amd64-undermydesk-freebsd Configured with: FreeBSD/amd64 system compiler Thread model: posix gcc version 4.2.1 20070831 patched [FreeBSD] FreeBSD 9.1 seems to be the only platform on which this bug appears. The code works as expected on Linux and OS X. According to a commenter, FreeBSD 9.0 works as expected too. According to another commenter the code fails on FreeBSD 9.1 with Clang too. Fix: Patch attached with submission follows: How-To-Repeat: See attached C++ program.
This bug is probably well understood by now, but here is a minimal testcase for it (no includes, as few C++ features as possible): extern "C++" { namespace std { class exception { const char* name() const { } }; class bad_cast : public exception { }; } } class foo { public: virtual ~foo() { } }; class bar: public foo { public: int val; bar(): val(123) { } }; static void cast_test(const foo &f) { try { const bar &b = dynamic_cast<const bar &>(f); } catch (const std::bad_cast &) { } } int main() { foo f; cast_test(f); } -- Eitan Adler
Author: theraven Date: Mon Jan 28 11:12:49 2013 New Revision: 246028 URL: http://svnweb.freebsd.org/changeset/base/246028 Log: Fix some symbol version mismatches between libstdc++ and libsupc++/libcxxrt that were causing the runtime and STL libraries to see different versions of various classes and functions when libstdc++ is used as a filter. Note: This changes the ABI for libcxxrt, but libcxxrt is currently only in -STABLE for testing and is not used by anything unless explicitly enabled by the end user. No default compiler configurations use it. libc++ will need to be recompiled after this change. make buildworld will do this automatically, but make in lib/libc++ will not necessarily work unless the new libcxxrt is installed first. PR: kern/171610, stand/175453 Reviewed by: kib MFC after: 1 week Modified: head/gnu/lib/libsupc++/Version.map head/lib/libcxxrt/Version.map Modified: head/gnu/lib/libsupc++/Version.map ============================================================================== --- head/gnu/lib/libsupc++/Version.map Mon Jan 28 10:52:24 2013 (r246027) +++ head/gnu/lib/libsupc++/Version.map Mon Jan 28 11:12:49 2013 (r246028) @@ -142,8 +142,37 @@ GLIBCXX_3.4 { _ZdaPvRKSt9nothrow_t; _ZdlPv; _ZdlPvRKSt9nothrow_t; + extern "C++" { + std::set_new_handler*; + std::set_terminate*; + std::set_unexpected*; + + std::bad_alloc; + std::bad_cast; + std::exception*; + + "typeinfo for std::bad_alloc"; + "typeinfo for std::bad_cast"; + "typeinfo for std::exception"; + + "typeinfo name for std::bad_alloc"; + "typeinfo name for std::bad_cast"; + "typeinfo name for std::exception"; + + "vtable for std::bad_alloc"; + "vtable for std::bad_cast"; + "vtable for std::exception"; + }; }; +GLIBCXX_3.4.9 { + extern "C++" { + "std::bad_alloc::what() const"; + "std::bad_cast::what() const"; + "std::bad_typeid::what() const"; + }; +} GLIBCXX_3.4; + CXXABI_1.3.1 { __cxa_get_exception_ptr; Modified: head/lib/libcxxrt/Version.map ============================================================================== --- head/lib/libcxxrt/Version.map Mon Jan 28 10:52:24 2013 (r246027) +++ head/lib/libcxxrt/Version.map Mon Jan 28 11:12:49 2013 (r246028) @@ -209,18 +209,7 @@ CXXABI_1.3 { "std::type_info::type_info(std::type_info const&)"; "std::type_info::type_info(std::type_info const&)"; - "std::type_info::~type_info()"; - "std::type_info::~type_info()"; - "std::type_info::~type_info()"; "std::type_info::operator=(std::type_info const&)"; - "std::unexpected()"; - "std::get_terminate()"; - "std::set_terminate(void (*)())"; - "std::get_unexpected()"; - "std::set_unexpected(void (*)())"; - "std::set_new_handler(void (*)())"; - "std::uncaught_exception()"; - "std::terminate()"; # Extensions @@ -243,67 +232,22 @@ CXXABI_1.3.1 { CXXRT_1.0 { extern "C++" { - "std::bad_cast::what() const"; - "std::bad_typeid::what() const"; - "std::bad_alloc::what() const"; - "std::exception::what() const"; "std::type_info::name() const"; "std::type_info::before(std::type_info const&) const"; "std::type_info::operator==(std::type_info const&) const"; "std::type_info::operator!=(std::type_info const&) const"; - "std::bad_typeid::bad_typeid(std::bad_typeid const&)"; - "std::bad_typeid::bad_typeid()"; - "std::bad_typeid::bad_typeid(std::bad_typeid const&)"; - "std::bad_typeid::bad_typeid()"; - "std::bad_typeid::~bad_typeid()"; - "std::bad_typeid::~bad_typeid()"; - "std::bad_typeid::~bad_typeid()"; - "std::bad_typeid::operator=(std::bad_typeid const&)"; "std::bad_cast::bad_cast(std::bad_cast const&)"; "std::bad_cast::bad_cast()"; "std::bad_cast::bad_cast(std::bad_cast const&)"; "std::bad_cast::bad_cast()"; - "std::bad_cast::~bad_cast()"; - "std::bad_cast::~bad_cast()"; - "std::bad_cast::~bad_cast()"; "std::bad_cast::operator=(std::bad_cast const&)"; - "std::bad_alloc::bad_alloc(std::bad_alloc const&)"; - "std::bad_alloc::bad_alloc()"; - "std::bad_alloc::bad_alloc(std::bad_alloc const&)"; - "std::bad_alloc::bad_alloc()"; - "std::bad_alloc::~bad_alloc()"; - "std::bad_alloc::~bad_alloc()"; - "std::bad_alloc::~bad_alloc()"; - "std::bad_alloc::operator=(std::bad_alloc const&)"; "std::exception::exception(std::exception const&)"; "std::exception::exception()"; "std::exception::exception(std::exception const&)"; "std::exception::exception()"; - "std::exception::~exception()"; - "std::exception::~exception()"; - "std::exception::~exception()"; "std::exception::operator=(std::exception const&)"; - "vtable for std::bad_typeid"; - "vtable for std::bad_cast"; - "vtable for std::bad_alloc"; - "vtable for std::exception"; - "vtable for std::type_info"; - "typeinfo for std::bad_typeid"; - "typeinfo for std::bad_cast"; - "typeinfo for std::bad_alloc"; - "typeinfo for std::exception"; - "typeinfo for std::type_info"; - "typeinfo name for std::bad_typeid"; - "typeinfo name for std::bad_cast"; - "typeinfo name for std::bad_alloc"; - "typeinfo name for std::exception"; - "typeinfo name for std::type_info"; - - "std::type_info::__is_function_p() const"; - "std::type_info::__do_upcast(__cxxabiv1::__class_type_info const*, void**) const"; - "std::type_info::__is_pointer_p() const"; @@ -317,6 +261,7 @@ CXXRT_1.0 { } CXXABI_1.3.1; + GLIBCXX_3.4 { extern "C++" { "operator delete[](void*)"; @@ -327,5 +272,50 @@ GLIBCXX_3.4 { "operator new[](unsigned long)"; "operator new(unsigned long)"; "operator new(unsigned long, std::nothrow_t const&)"; + + "std::unexpected()"; + "std::get_terminate()"; + "std::get_unexpected()"; + "std::uncaught_exception()"; + "std::terminate()"; + + "std::type_info::~type_info()"; + "std::bad_cast::~bad_cast()"; + "std::exception::~exception()"; + + std::set_new_handler*; + std::set_terminate*; + std::set_unexpected*; + std::exception*; + std::bad_alloc; + std::bad_typeid; + std::type_info*; + + "vtable for std::bad_alloc"; + "vtable for std::bad_cast"; + "vtable for std::bad_typeid"; + "vtable for std::exception"; + "vtable for std::type_info"; + + "typeinfo for std::bad_alloc"; + "typeinfo for std::bad_typeid"; + "typeinfo for std::exception"; + "typeinfo for std::bad_cast"; + "typeinfo for std::exception"; + "typeinfo for std::type_info"; + "typeinfo name for std::bad_typeid"; + "typeinfo name for std::bad_cast"; + "typeinfo name for std::exception"; + "typeinfo name for std::type_info"; + }; }; + +GLIBCXX_3.4.9 { + extern "C++" { + "std::bad_typeid::what() const"; + "std::bad_cast::what() const"; + "std::bad_alloc::what() const"; + }; +} GLIBCXX_3.4; + _______________________________________________ svn-src-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscribe@freebsd.org"
Author: dim Date: Tue Feb 5 19:10:50 2013 New Revision: 246368 URL: http://svnweb.freebsd.org/changeset/base/246368 Log: MFC r246028 (by theraven): Fix some symbol version mismatches between libstdc++ and libsupc++/libcxxrt that were causing the runtime and STL libraries to see different versions of various classes and functions when libstdc++ is used as a filter. Note: This changes the ABI for libcxxrt, but libcxxrt is currently only in -STABLE for testing and is not used by anything unless explicitly enabled by the end user. No default compiler configurations use it. libc++ will need to be recompiled after this change. make buildworld will do this automatically, but make in lib/libc++ will not necessarily work unless the new libcxxrt is installed first. PR: kern/171610, stand/175453 Reviewed by: kib MFC r246297: Add several missing symbols to libcxxrt's symbol version map, and remove a few duplicates. This should fix building world with -stdlib=libc++ after r246028. Submitted by: Yamaya Takashi <yamayan@kbh.biglobe.ne.jp> Modified: stable/9/gnu/lib/libsupc++/Version.map stable/9/lib/libcxxrt/Version.map Directory Properties: stable/9/gnu/lib/libsupc++/ (props changed) stable/9/lib/libcxxrt/ (props changed) Modified: stable/9/gnu/lib/libsupc++/Version.map ============================================================================== --- stable/9/gnu/lib/libsupc++/Version.map Tue Feb 5 18:55:09 2013 (r246367) +++ stable/9/gnu/lib/libsupc++/Version.map Tue Feb 5 19:10:50 2013 (r246368) @@ -142,8 +142,37 @@ GLIBCXX_3.4 { _ZdaPvRKSt9nothrow_t; _ZdlPv; _ZdlPvRKSt9nothrow_t; + extern "C++" { + std::set_new_handler*; + std::set_terminate*; + std::set_unexpected*; + + std::bad_alloc; + std::bad_cast; + std::exception*; + + "typeinfo for std::bad_alloc"; + "typeinfo for std::bad_cast"; + "typeinfo for std::exception"; + + "typeinfo name for std::bad_alloc"; + "typeinfo name for std::bad_cast"; + "typeinfo name for std::exception"; + + "vtable for std::bad_alloc"; + "vtable for std::bad_cast"; + "vtable for std::exception"; + }; }; +GLIBCXX_3.4.9 { + extern "C++" { + "std::bad_alloc::what() const"; + "std::bad_cast::what() const"; + "std::bad_typeid::what() const"; + }; +} GLIBCXX_3.4; + CXXABI_1.3.1 { __cxa_get_exception_ptr; Modified: stable/9/lib/libcxxrt/Version.map ============================================================================== --- stable/9/lib/libcxxrt/Version.map Tue Feb 5 18:55:09 2013 (r246367) +++ stable/9/lib/libcxxrt/Version.map Tue Feb 5 19:10:50 2013 (r246368) @@ -208,19 +208,7 @@ CXXABI_1.3 { "typeinfo name for __cxxabiv1::__vmi_class_type_info"; "std::type_info::type_info(std::type_info const&)"; - "std::type_info::type_info(std::type_info const&)"; - "std::type_info::~type_info()"; - "std::type_info::~type_info()"; - "std::type_info::~type_info()"; "std::type_info::operator=(std::type_info const&)"; - "std::unexpected()"; - "std::get_terminate()"; - "std::set_terminate(void (*)())"; - "std::get_unexpected()"; - "std::set_unexpected(void (*)())"; - "std::set_new_handler(void (*)())"; - "std::uncaught_exception()"; - "std::terminate()"; # Extensions @@ -243,69 +231,22 @@ CXXABI_1.3.1 { CXXRT_1.0 { extern "C++" { - "std::bad_cast::what() const"; - "std::bad_typeid::what() const"; - "std::bad_alloc::what() const"; - "std::exception::what() const"; "std::type_info::name() const"; "std::type_info::before(std::type_info const&) const"; "std::type_info::operator==(std::type_info const&) const"; "std::type_info::operator!=(std::type_info const&) const"; - "std::bad_typeid::bad_typeid(std::bad_typeid const&)"; - "std::bad_typeid::bad_typeid()"; - "std::bad_typeid::bad_typeid(std::bad_typeid const&)"; - "std::bad_typeid::bad_typeid()"; - "std::bad_typeid::~bad_typeid()"; - "std::bad_typeid::~bad_typeid()"; - "std::bad_typeid::~bad_typeid()"; - "std::bad_typeid::operator=(std::bad_typeid const&)"; "std::bad_cast::bad_cast(std::bad_cast const&)"; "std::bad_cast::bad_cast()"; - "std::bad_cast::bad_cast(std::bad_cast const&)"; - "std::bad_cast::bad_cast()"; - "std::bad_cast::~bad_cast()"; - "std::bad_cast::~bad_cast()"; - "std::bad_cast::~bad_cast()"; "std::bad_cast::operator=(std::bad_cast const&)"; - "std::bad_alloc::bad_alloc(std::bad_alloc const&)"; - "std::bad_alloc::bad_alloc()"; - "std::bad_alloc::bad_alloc(std::bad_alloc const&)"; - "std::bad_alloc::bad_alloc()"; - "std::bad_alloc::~bad_alloc()"; - "std::bad_alloc::~bad_alloc()"; - "std::bad_alloc::~bad_alloc()"; - "std::bad_alloc::operator=(std::bad_alloc const&)"; - "std::exception::exception(std::exception const&)"; - "std::exception::exception()"; + "std::bad_typeid::bad_typeid(std::bad_typeid const&)"; + "std::bad_typeid::bad_typeid()"; + "std::bad_typeid::operator=(std::bad_typeid const&)"; "std::exception::exception(std::exception const&)"; "std::exception::exception()"; - "std::exception::~exception()"; - "std::exception::~exception()"; - "std::exception::~exception()"; "std::exception::operator=(std::exception const&)"; - - - "vtable for std::bad_typeid"; - "vtable for std::bad_cast"; - "vtable for std::bad_alloc"; - "vtable for std::exception"; - "vtable for std::type_info"; - "typeinfo for std::bad_typeid"; - "typeinfo for std::bad_cast"; - "typeinfo for std::bad_alloc"; - "typeinfo for std::exception"; - "typeinfo for std::type_info"; - "typeinfo name for std::bad_typeid"; - "typeinfo name for std::bad_cast"; - "typeinfo name for std::bad_alloc"; - "typeinfo name for std::exception"; - "typeinfo name for std::type_info"; - - "std::type_info::__is_function_p() const"; - "std::type_info::__do_upcast(__cxxabiv1::__class_type_info const*, void**) const"; - "std::type_info::__is_pointer_p() const"; - - + "std::bad_alloc::bad_alloc(std::bad_alloc const&)"; + "std::bad_alloc::bad_alloc()"; + "std::bad_alloc::operator=(std::bad_alloc const&)"; }; __cxa_allocate_dependent_exception; @@ -317,6 +258,7 @@ CXXRT_1.0 { } CXXABI_1.3.1; + GLIBCXX_3.4 { extern "C++" { "operator delete[](void*)"; @@ -327,5 +269,51 @@ GLIBCXX_3.4 { "operator new[](unsigned long)"; "operator new(unsigned long)"; "operator new(unsigned long, std::nothrow_t const&)"; + + "std::unexpected()"; + "std::get_terminate()"; + "std::get_unexpected()"; + "std::uncaught_exception()"; + "std::terminate()"; + + "std::type_info::~type_info()"; + "std::bad_cast::~bad_cast()"; + "std::bad_typeid::~bad_typeid()"; + "std::exception::~exception()"; + "std::bad_alloc::~bad_alloc()"; + + "std::exception::what() const"; + + std::set_new_handler*; + std::set_terminate*; + std::set_unexpected*; + std::type_info::__*; + + "vtable for std::bad_alloc"; + "vtable for std::bad_cast"; + "vtable for std::bad_typeid"; + "vtable for std::exception"; + "vtable for std::type_info"; + + "typeinfo for std::bad_alloc"; + "typeinfo for std::bad_typeid"; + "typeinfo for std::bad_cast"; + "typeinfo for std::exception"; + "typeinfo for std::type_info"; + "typeinfo name for std::bad_alloc"; + "typeinfo name for std::bad_typeid"; + "typeinfo name for std::bad_cast"; + "typeinfo name for std::exception"; + "typeinfo name for std::type_info"; + }; }; + +GLIBCXX_3.4.9 { + extern "C++" { + "std::bad_typeid::what() const"; + "std::bad_cast::what() const"; + "std::bad_alloc::what() const"; + }; +} GLIBCXX_3.4; +
I think it would be worth adding this to the errata document for 9.1. The patch for stable/9 applies cleanly to 9.1 and I'm working on testing it right now. -GAWollman
State Changed From-To: open->patched Fixed in HEAD and stable/9, will be in 9.2 release.
As per previous comment, merged to 9-STABLE prior to 9.2