Fix failure to run tests when CFLAGS contains -DNDEBUG (Bug 25251)

Message ID 35485007-9fa2-30d8-2a28-3f6ad577ee8e@redhat.com
State Superseded
Headers

Commit Message

Carlos O'Donell Dec. 4, 2019, 2:44 p.m. UTC
  On 12/4/19 2:31 AM, Florian Weimer wrote:
> * Carlos O'Donell:
> 
>> How is this v2 with a better commit message?
> 
> Sorry, why has -DNDEBUG got anything with -march=i486 (sic) or -Os?
> I think you should mention -DNDEBUG only.
> 
> The comment should probably mention CFLAGS and -DNDEBUG, because that's
> the common case.

Ah, I see your point. Cleaned up. I filed a new bug for this user-visible
build bug. The following patch fixes the issue, and commit message update.

No regressions on a build with -DNDEBUG.

OK for master?

From 080292f03e7489910750d9fe79e652aa8636bc84 Mon Sep 17 00:00:00 2001
From: Carlos O'Donell <carlos@redhat.com>
Date: Tue, 3 Dec 2019 15:42:24 -0500
Subject: [PATCH] Fix failure to run tests when CFLAGS contains -DNDEBUG (Bug
 25251)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Building tests with -DNDEBUG in CFLAGS, gcc 9.2.1 issues the following error:
tst-assert-c++.cc: In function ‘int do_test()’:
tst-assert-c++.cc:66:12: error: unused variable ‘value’ [-Werror=unused-variable]
   66 |     no_int value;
      |            ^~~~~
tst-assert-c++.cc:71:18: error: unused variable ‘value’ [-Werror=unused-variable]
   71 |     bool_and_int value;
      |                  ^~~~~

The assert has been disabled by building glibc with CFLAGS, CXXFLAGS,
and CPPFLAGS with -DNDEBUG which removes the assert and leaves the
value unused.

We never want the assert disabled because that's the point of the
test, so we undefine NDEBUG before including assert.h to ensure that
we get assert correctly defined.
---
 assert/tst-assert-c++.cc | 3 +++
 1 file changed, 3 insertions(+)
  

Patch

diff --git a/assert/tst-assert-c++.cc b/assert/tst-assert-c++.cc
index 41cb487512..a175f5e961 100644
--- a/assert/tst-assert-c++.cc
+++ b/assert/tst-assert-c++.cc
@@ -16,6 +16,9 @@ 
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+/* We do not want the compiler or any other pre-included header from
+   removing the assert we want to test, so undefine NDEBUG right now.  */
+#undef NDEBUG
 #include <assert.h>
 
 /* The C++ standard requires that if the assert argument is a constant