From: Jonathan Wakely <jwakely@redhat.com>
To: libstdc++@gcc.gnu.org, gcc-patches@gcc.gnu.org
Subject: [committed] libstdc++: Fix std::type_info::before for ARM [PR103240]
Date: Wed, 17 Nov 2021 17:25:18 +0000 [thread overview]
Message-ID: <20211117172518.4166459-1-jwakely@redhat.com> (raw)
Tested powerpc64le-linux, and briefly checkd on armv7hl-linux-gnueabi,
pushed to trunk.
The r179236 fix for std::type_info::operator== should also have been
applied to std::type_info::before. Otherwise two distinct types can
compare equivalent due to using a string comparison, when they should do
a pointer comparison.
libstdc++-v3/ChangeLog:
PR libstdc++/103240
* libsupc++/tinfo2.cc (type_info::before): Use unadjusted name
to check for the '*' prefix.
* testsuite/util/testsuite_shared.cc: Add type_info object for
use in new test.
* testsuite/18_support/type_info/103240.cc: New test.
---
libstdc++-v3/libsupc++/tinfo2.cc | 5 ++-
.../testsuite/18_support/type_info/103240.cc | 36 +++++++++++++++++++
.../testsuite/util/testsuite_shared.cc | 12 +++++++
3 files changed, 52 insertions(+), 1 deletion(-)
create mode 100644 libstdc++-v3/testsuite/18_support/type_info/103240.cc
diff --git a/libstdc++-v3/libsupc++/tinfo2.cc b/libstdc++-v3/libsupc++/tinfo2.cc
index b587cfd037b..d02021fe538 100644
--- a/libstdc++-v3/libsupc++/tinfo2.cc
+++ b/libstdc++-v3/libsupc++/tinfo2.cc
@@ -36,7 +36,10 @@ type_info::before (const type_info &arg) const _GLIBCXX_NOEXCEPT
#if __GXX_MERGED_TYPEINFO_NAMES
return name () < arg.name ();
#else
- return (name ()[0] == '*') ? name () < arg.name ()
+ /* The name() method will strip any leading '*' prefix. Therefore
+ take care to look at __name rather than name() when looking for
+ the "pointer" prefix. */
+ return (__name[0] == '*') ? name () < arg.name ()
: __builtin_strcmp (name (), arg.name ()) < 0;
#endif
}
diff --git a/libstdc++-v3/testsuite/18_support/type_info/103240.cc b/libstdc++-v3/testsuite/18_support/type_info/103240.cc
new file mode 100644
index 00000000000..3d5968ac25c
--- /dev/null
+++ b/libstdc++-v3/testsuite/18_support/type_info/103240.cc
@@ -0,0 +1,36 @@
+// { dg-do run }
+// { dg-require-sharedlib "" }
+// { dg-options "./testsuite_shared.so" }
+
+#include <typeinfo>
+#include <testsuite_hooks.h>
+
+namespace __gnu_test
+{
+namespace
+{
+ struct S { };
+ struct T { };
+}
+
+// Defined in testsuite_shared.so, referring to private type in that library
+// with the same mangled name as __gnu_test::<anonymous>::S defined here.
+extern const std::type_info& pr103240_private_S;
+}
+
+const std::type_info& private_S = __gnu_test::pr103240_private_S;
+const std::type_info& local_S = typeid(__gnu_test::S);
+const std::type_info& local_T = typeid(__gnu_test::T);
+
+int main()
+{
+ VERIFY( local_S == local_S );
+ VERIFY( ! local_S.before(local_S) );
+
+ VERIFY( local_S != local_T );
+ VERIFY( local_S.before(local_T) || local_T.before(local_S) );
+
+ VERIFY( local_S != private_S );
+ // PR libstdc++/103240
+ VERIFY( local_S.before(private_S) || private_S.before(local_S) );
+}
diff --git a/libstdc++-v3/testsuite/util/testsuite_shared.cc b/libstdc++-v3/testsuite/util/testsuite_shared.cc
index c4a7ed4abe5..8c10534c511 100644
--- a/libstdc++-v3/testsuite/util/testsuite_shared.cc
+++ b/libstdc++-v3/testsuite/util/testsuite_shared.cc
@@ -23,6 +23,9 @@
#include <map>
#include <ext/mt_allocator.h>
#include <bits/functexcept.h>
+#if __cpp_rtti
+# include <typeinfo>
+#endif
namespace __gnu_test
{
@@ -130,4 +133,13 @@ try_function_random_fail()
}
#endif
+#if __cpp_rtti
+// PR libstdc++/103240
+namespace
+{
+ struct S { };
+}
+const std::type_info& pr103240_private_S = typeid(S);
+#endif
+
} // end namepace __gnu_test
--
2.31.1
reply other threads:[~2021-11-17 17:25 UTC|newest]
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