This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH] detect incompatible aliases (PR c/81854)
- From: Jonathan Wakely <jwakely at redhat dot com>
- To: Martin Sebor <msebor at gmail dot com>
- Cc: Gcc Patch List <gcc-patches at gcc dot gnu dot org>, Joseph Myers <joseph at codesourcery dot com>, libstdc++ <libstdc++ at gcc dot gnu dot org>
- Date: Fri, 18 Aug 2017 14:10:46 +0100
- Subject: Re: [PATCH] detect incompatible aliases (PR c/81854)
- Authentication-results: sourceware.org; auth=none
- Authentication-results: ext-mx06.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com
- Authentication-results: ext-mx06.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=jwakely at redhat dot com
- Dmarc-filter: OpenDMARC Filter v1.3.2 mx1.redhat.com DBA17356F6
- References: <b8534b3c-9ffd-5a1c-d5e7-536548c9b742@gmail.com>
On 17/08/17 21:21 -0600, Martin Sebor wrote:
Joseph, while looking into implementing enhancement your request
pr81824 I noticed that GCC silently accepts incompatible alias
declarations (pr81854) so as sort of a proof-concept for the
former I enhanced the checking already done for other kinds of
incompatibilities to also detect those mentioned in the latter
bug. Attached is this patch, tested on x85_64-linux.
Jonathan, the patch requires suppressing the warning in libstdc++
compatibility symbol definitions in compatibility.cc. I couldn't
find a way to do it without the suppression but I'd be happy to
try again if you have an idea for how.
Doing it that way is fine, but ...
diff --git a/libstdc++-v3/src/c++98/compatibility.cc b/libstdc++-v3/src/c++98/compatibility.cc
index 381f4c4..5f56b9e 100644
--- a/libstdc++-v3/src/c++98/compatibility.cc
+++ b/libstdc++-v3/src/c++98/compatibility.cc
@@ -213,6 +213,11 @@ _ZNSt19istreambuf_iteratorIcSt11char_traitsIcEEppEv
_ZNSt19istreambuf_iteratorIwSt11char_traitsIwEEppEv
*/
+// Disable warning about declaring aliases between functions with
+// incompatible types.
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wattributes"
+
Could this be moved closer to the point where it's needed?
It's not needed until after line 361, right?
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
@@ -509,6 +514,9 @@ _GLIBCXX_MATHL_WRAPPER1 (tan, GLIBCXX_3.4);
#endif
#endif // _GLIBCXX_LONG_DOUBLE_COMPAT
+// Restore disable -Wattributes
+#pragma GCC diagnostic pop
+
#endif
#ifdef _GLIBCXX_LONG_DOUBLE_COMPAT