diff mbox series

[2/4] libstdc++: Add a test for <version> FTM redefinitions

Message ID 20230404230950.158556-2-arsen@aarsen.me
State Accepted
Headers
Series [1/4] libstdc++: Harmonize <version> and other headers |

Checks

Context Check Description
snail/gcc-patch-check success Github commit url

Commit Message

Arsen Arsenović April 4, 2023, 11:09 p.m. UTC 
  This test detects redefinitions by compiling stdc++.h with
-Wsystem-headers.  Thanks Patrick Palka for the suggestion.

libstdc++-v3/ChangeLog:

	* testsuite/17_intro/versionconflict.cc: New test.
---
 libstdc++-v3/testsuite/17_intro/versionconflict.cc | 6 ++++++
 1 file changed, 6 insertions(+)
 create mode 100644 libstdc++-v3/testsuite/17_intro/versionconflict.cc

Comments

Jonathan Wakely April 5, 2023, 10:59 a.m. UTC | #1 
On 05/04/23 01:09 +0200, Arsen Arsenović wrote:
>This test detects redefinitions by compiling stdc++.h with
>-Wsystem-headers.  Thanks Patrick Palka for the suggestion.
>
>libstdc++-v3/ChangeLog:
>
>	* testsuite/17_intro/versionconflict.cc: New test.
>---
> libstdc++-v3/testsuite/17_intro/versionconflict.cc | 6 ++++++
> 1 file changed, 6 insertions(+)
> create mode 100644 libstdc++-v3/testsuite/17_intro/versionconflict.cc
>
>diff --git a/libstdc++-v3/testsuite/17_intro/versionconflict.cc b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
>new file mode 100644
>index 00000000000..4191c7a2b08
>--- /dev/null
>+++ b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
>@@ -0,0 +1,6 @@
>+// { dg-do preprocess }
>+// { dg-additional-options "-Wsystem-headers -Werror" }
>+
>+// Test for redefinitions of FTMs using bits/stdc++.h.
>+#include <bits/stdc++.h>
>+#include <version>

I'm concerned that this will fail if libc headers have macro
redefinition errors, or anything else that would usually be ignored.

We could make it more robust by changing <version> like so:

--- a/libstdc++-v3/include/std/version
+++ b/libstdc++-v3/include/std/version
@@ -30,7 +30,9 @@
  #ifndef _GLIBCXX_VERSION_INCLUDED
  #define _GLIBCXX_VERSION_INCLUDED
  
+#ifndef _GLIBCXX_TESTING_SYSHDR
  #pragma GCC system_header
+#endif
  
  #include <bits/c++config.h>
  
Then the test could define that macro instead of using -Wsystem-headers.

Could you see if that works?
Arsen Arsenović April 5, 2023, 11:31 a.m. UTC | #2 
Jonathan Wakely <jwakely@redhat.com> writes:

> On 05/04/23 01:09 +0200, Arsen Arsenović wrote:
>>This test detects redefinitions by compiling stdc++.h with
>>-Wsystem-headers.  Thanks Patrick Palka for the suggestion.
>>
>>libstdc++-v3/ChangeLog:
>>
>>	* testsuite/17_intro/versionconflict.cc: New test.
>>---
>> libstdc++-v3/testsuite/17_intro/versionconflict.cc | 6 ++++++
>> 1 file changed, 6 insertions(+)
>> create mode 100644 libstdc++-v3/testsuite/17_intro/versionconflict.cc
>>
>>diff --git a/libstdc++-v3/testsuite/17_intro/versionconflict.cc b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
>>new file mode 100644
>>index 00000000000..4191c7a2b08
>>--- /dev/null
>>+++ b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
>>@@ -0,0 +1,6 @@
>>+// { dg-do preprocess }
>>+// { dg-additional-options "-Wsystem-headers -Werror" }
>>+
>>+// Test for redefinitions of FTMs using bits/stdc++.h.
>>+#include <bits/stdc++.h>
>>+#include <version>
>
> I'm concerned that this will fail if libc headers have macro
> redefinition errors, or anything else that would usually be ignored.
>
> We could make it more robust by changing <version> like so:
>
> --- a/libstdc++-v3/include/std/version
> +++ b/libstdc++-v3/include/std/version
> @@ -30,7 +30,9 @@
>  #ifndef _GLIBCXX_VERSION_INCLUDED
>  #define _GLIBCXX_VERSION_INCLUDED
>  +#ifndef _GLIBCXX_TESTING_SYSHDR
>  #pragma GCC system_header
> +#endif
>    #include <bits/c++config.h>
>  Then the test could define that macro instead of using -Wsystem-headers.
>
> Could you see if that works?

Good idea.  Both the positive and negative cases work when implemented
like this:
From 98d302bab9a87d3f2daecf9d54d62f33ba216673 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Arsen=20Arsenovi=C4=87?= <arsen@aarsen.me>
Date: Wed, 8 Mar 2023 17:01:24 +0100
Subject: [PATCH 2/4] libstdc++: Add a test for <version> FTM redefinitions

This test detects redefinitions by compiling stdc++.h with
-Wsystem-headers.  Thanks Patrick Palka for the suggestion.

libstdc++-v3/ChangeLog:

	* testsuite/17_intro/versionconflict.cc: New test.
---
 libstdc++-v3/include/std/version                   | 5 ++++-
 libstdc++-v3/testsuite/17_intro/versionconflict.cc | 7 +++++++
 2 files changed, 11 insertions(+), 1 deletion(-)
 create mode 100644 libstdc++-v3/testsuite/17_intro/versionconflict.cc

diff --git a/libstdc++-v3/include/std/version b/libstdc++-v3/include/std/version
index cdd24248c57..1069bc6c9f6 100644
--- a/libstdc++-v3/include/std/version
+++ b/libstdc++-v3/include/std/version
@@ -30,7 +30,10 @@
 #ifndef _GLIBCXX_VERSION_INCLUDED
 #define _GLIBCXX_VERSION_INCLUDED
 
-#pragma GCC system_header
+// To facilitate testsuite/17_intro/versionconflict.cc
+#ifndef _GLIBCXX_TESTING_SYSHDR
+# pragma GCC system_header
+#endif
 
 #include <bits/c++config.h>
 
diff --git a/libstdc++-v3/testsuite/17_intro/versionconflict.cc b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
new file mode 100644
index 00000000000..6c212980ab0
--- /dev/null
+++ b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
@@ -0,0 +1,7 @@
+// { dg-do preprocess }
+// { dg-additional-options "-Werror" }
+
+// Test for redefinitions of FTMs using bits/stdc++.h.
+#define _GLIBCXX_TESTING_SYSHDR
+#include <bits/stdc++.h>
+#include <version>
Arsen Arsenović April 5, 2023, 11:38 a.m. UTC | #3 
Arsen Arsenović via Libstdc++ <libstdc++@gcc.gnu.org> writes:

> Good idea.  Both the positive and negative cases work when implemented
> like this:
>
> From 98d302bab9a87d3f2daecf9d54d62f33ba216673 Mon Sep 17 00:00:00 2001
> From: =?UTF-8?q?Arsen=20Arsenovi=C4=87?= <arsen@aarsen.me>
> Date: Wed, 8 Mar 2023 17:01:24 +0100
> Subject: [PATCH 2/4] libstdc++: Add a test for <version> FTM redefinitions
>
> This test detects redefinitions by compiling stdc++.h with
> -Wsystem-headers.  Thanks Patrick Palka for the suggestion.
>
> libstdc++-v3/ChangeLog:
>
> 	* testsuite/17_intro/versionconflict.cc: New test.

I've forgotten to reword this after changing the logic.  New message:

commit dcd7bed33cc274e8f3565ad02fb1fbc04bc845fb
Author: Arsen Arsenović <arsen@aarsen.me>
Date:   Wed Mar 8 17:01:24 2023 +0100

    libstdc++: Add a test for <version> FTM redefinitions
    
    This test detects redefinitions by compiling stdc++.h and <version>,
    by disabling the system_header pragma on the latter, to allow
    warnings in it.  Thanks Patrick Palka for the suggestion.
    
    libstdc++-v3/ChangeLog:
    
            * testsuite/17_intro/versionconflict.cc: New test.
Jonathan Wakely April 5, 2023, 12:07 p.m. UTC | #4 
On Wed, 5 Apr 2023 at 12:39, Arsen Arsenović <arsen@aarsen.me> wrote:
>
>
> Arsen Arsenović via Libstdc++ <libstdc++@gcc.gnu.org> writes:
>
> > Good idea.  Both the positive and negative cases work when implemented
> > like this:
> >
> > From 98d302bab9a87d3f2daecf9d54d62f33ba216673 Mon Sep 17 00:00:00 2001
> > From: =?UTF-8?q?Arsen=20Arsenovi=C4=87?= <arsen@aarsen.me>
> > Date: Wed, 8 Mar 2023 17:01:24 +0100
> > Subject: [PATCH 2/4] libstdc++: Add a test for <version> FTM redefinitions
> >
> > This test detects redefinitions by compiling stdc++.h with
> > -Wsystem-headers.  Thanks Patrick Palka for the suggestion.
> >
> > libstdc++-v3/ChangeLog:
> >
> >       * testsuite/17_intro/versionconflict.cc: New test.
>
> I've forgotten to reword this after changing the logic.  New message:
>
> commit dcd7bed33cc274e8f3565ad02fb1fbc04bc845fb
> Author: Arsen Arsenović <arsen@aarsen.me>
> Date:   Wed Mar 8 17:01:24 2023 +0100
>
>     libstdc++: Add a test for <version> FTM redefinitions
>
>     This test detects redefinitions by compiling stdc++.h and <version>,
>     by disabling the system_header pragma on the latter, to allow
>     warnings in it.  Thanks Patrick Palka for the suggestion.
>
>     libstdc++-v3/ChangeLog:
>
>             * testsuite/17_intro/versionconflict.cc: New test.


OK for trunk, thanks.
diff mbox series

Patch

diff --git a/libstdc++-v3/testsuite/17_intro/versionconflict.cc b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
new file mode 100644
index 00000000000..4191c7a2b08
--- /dev/null
+++ b/libstdc++-v3/testsuite/17_intro/versionconflict.cc
@@ -0,0 +1,6 @@ 
+// { dg-do preprocess }
+// { dg-additional-options "-Wsystem-headers -Werror" }
+
+// Test for redefinitions of FTMs using bits/stdc++.h.
+#include <bits/stdc++.h>
+#include <version>