From: Jonathan Wakely <jwakely@redhat.com>
To: Thomas Schwinge <thomas@codesourcery.com>
Cc: Martin Sebor <msebor@gmail.com>,
libstdc++@gcc.gnu.org, gcc-patches@gcc.gnu.org,
Marek Polacek <polacek@redhat.com>,
"Joseph S. Myers" <joseph@codesourcery.com>,
Jeff Law <law@redhat.com>
Subject: Re: [PR c/68966] Restore atomic builtins usage in libstdc++-v3
Date: Tue, 05 Apr 2016 19:04:00 -0000 [thread overview]
Message-ID: <20160405190419.GK5814@redhat.com> (raw)
In-Reply-To: <20160405180835.GJ5814@redhat.com>
[-- Attachment #1: Type: text/plain, Size: 625 bytes --]
On 05/04/16 19:08 +0100, Jonathan Wakely wrote:
>On 05/04/16 12:01 +0100, Jonathan Wakely wrote:
>>Well I guess it's mine, and this is a fairly serious regression (is it
>>tracked in Bugzilla anywhere?) so the patch is OK for trunk.
>
>This is now https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70554
I've committed this smaller change, which still tests atomics for
bool, but simply removes the uses of __atomic_fetch_add for bool.
During stage 1 we can revisit whether we want to do something more
invasive and stop testing for atomics that we don't actually need.
Tested ppc64le-linux, x86_64-linux, comitted to trunk.
[-- Attachment #2: patch.txt --]
[-- Type: text/x-patch, Size: 1263 bytes --]
commit 7591475c21a34bbcce6d225ea7640d35022fb8ff
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Tue Apr 5 19:16:05 2016 +0100
Restore atomic builtins usage in libstdc++-v3
PR libstdc++/70554
* acinclude.m4 (GLIBCXX_ENABLE_ATOMIC_BUILTINS): Don't test
__atomic_fetch_add for bool.
* configure: Regenerate.
diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4
index 95df24a..b0f88cb 100644
--- a/libstdc++-v3/acinclude.m4
+++ b/libstdc++-v3/acinclude.m4
@@ -3290,7 +3290,7 @@ AC_DEFUN([GLIBCXX_ENABLE_ATOMIC_BUILTINS], [
atomic_type c1;
atomic_type c2;
atomic_type c3(0);
- __atomic_fetch_add(&c1, c2, __ATOMIC_RELAXED);
+ // N.B. __atomic_fetch_add is not supported for bool.
__atomic_compare_exchange_n(&c1, &c2, c3, true, __ATOMIC_ACQ_REL,
__ATOMIC_RELAXED);
__atomic_test_and_set(&c1, __ATOMIC_RELAXED);
@@ -3375,7 +3375,7 @@ int main()
atomic_type c1;
atomic_type c2;
atomic_type c3(0);
- __atomic_fetch_add(&c1, c2, __ATOMIC_RELAXED);
+ // N.B. __atomic_fetch_add is not supported for bool.
__atomic_compare_exchange_n(&c1, &c2, c3, true, __ATOMIC_ACQ_REL,
__ATOMIC_RELAXED);
__atomic_test_and_set(&c1, __ATOMIC_RELAXED);
prev parent reply other threads:[~2016-04-05 19:04 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-23 4:46 [PATCH] c/68966 - atomic_fetch_* on atomic_bool not diagnosed Martin Sebor
2016-01-02 7:43 ` Jeff Law
2016-01-04 3:03 ` Martin Sebor
2016-01-04 15:22 ` Marek Polacek
2016-01-05 1:18 ` Martin Sebor
2016-01-05 10:51 ` Marek Polacek
2016-01-05 18:47 ` Martin Sebor
2016-01-06 11:50 ` Marek Polacek
2016-01-06 23:38 ` Martin Sebor
2016-01-07 0:08 ` Mike Stump
2016-01-07 12:07 ` Marek Polacek
2016-01-08 1:00 ` Martin Sebor
2016-03-21 12:35 ` [PR c/68966] Restore atomic builtins usage in libstdc++-v3 (was: [PATCH] c/68966 - atomic_fetch_* on atomic_bool not diagnosed) Thomas Schwinge
2016-03-21 15:12 ` Jonathan Wakely
2016-03-21 16:04 ` [PR c/68966] Restore atomic builtins usage in libstdc++-v3 Thomas Schwinge
2016-04-05 11:01 ` Jonathan Wakely
2016-04-05 18:08 ` Jonathan Wakely
2016-04-05 19:04 ` Jonathan Wakely [this message]
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