<sys/cdefs.h>: Inhibit macro expansion for __glibc_has_include
diff mbox series

Message ID 87a7em6ben.fsf@oldenburg2.str.redhat.com
State New
Headers show
Series
  • <sys/cdefs.h>: Inhibit macro expansion for __glibc_has_include
Related show

Commit Message

Florian Weimer June 12, 2019, 4:01 p.m. UTC
This is currently ineffective with GCC because of GC PR 80005, but
it makes sense to anticipate a fix for this defect.

Suggested by Zack Weinberg.

2019-06-12  Florian Weimer  <fweimer@redhat.com>

	* misc/sys/cdefs.h (__glibc_has_include): Do not use a
	function-like macro, so that __has_include can inhibit expansion
	of its argument.

Comments

Florian Weimer June 14, 2019, 2:09 p.m. UTC | #1
* Florian Weimer:

> This is currently ineffective with GCC because of GC PR 80005, but
> it makes sense to anticipate a fix for this defect.
>
> Suggested by Zack Weinberg.
>
> 2019-06-12  Florian Weimer  <fweimer@redhat.com>
>
> 	* misc/sys/cdefs.h (__glibc_has_include): Do not use a
> 	function-like macro, so that __has_include can inhibit expansion
> 	of its argument.
>
> diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
> index 638872b87b..ed146ce20b 100644
> --- a/misc/sys/cdefs.h
> +++ b/misc/sys/cdefs.h
> @@ -413,7 +413,7 @@
>  #endif
>  
>  #ifdef __has_include
> -# define __glibc_has_include(header)	__has_include (header)
> +# define __glibc_has_include __has_include
>  #else
>  # define __glibc_has_include(header)	0
>  #endif

This is what I plan to commit shortly.

I don't want to mention the GCC PR in the public header because it will
be outdated soon (I hope).

Thanks,
Florian

<sys/cdefs.h>: Inhibit macro expansion for __glibc_has_include

This is currently ineffective with GCC because of GCC PR 80005, but
it makes sense to anticipate a fix for this defect.

Suggested by Zack Weinberg.

2019-06-14  Florian Weimer  <fweimer@redhat.com>

	* misc/sys/cdefs.h (__glibc_has_include): Do not use a
	function-like macro, so that __has_include can inhibit expansion
	of its argument.

diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
index 638872b87b..f1bd994a10 100644
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -413,7 +413,9 @@
 #endif
 
 #ifdef __has_include
-# define __glibc_has_include(header)	__has_include (header)
+/* Do not use a function-like macro, so that __has_include can inhibit
+   macro expansion.  */
+# define __glibc_has_include __has_include
 #else
 # define __glibc_has_include(header)	0
 #endif
Carlos O'Donell June 14, 2019, 2:18 p.m. UTC | #2
On 6/14/19 10:09 AM, Florian Weimer wrote:
> * Florian Weimer:
> 
>> This is currently ineffective with GCC because of GC PR 80005, but
>> it makes sense to anticipate a fix for this defect.
>>
>> Suggested by Zack Weinberg.
>>
>> 2019-06-12  Florian Weimer  <fweimer@redhat.com>
>>
>> 	* misc/sys/cdefs.h (__glibc_has_include): Do not use a
>> 	function-like macro, so that __has_include can inhibit expansion
>> 	of its argument.
>>
>> diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
>> index 638872b87b..ed146ce20b 100644
>> --- a/misc/sys/cdefs.h
>> +++ b/misc/sys/cdefs.h
>> @@ -413,7 +413,7 @@
>>  #endif
>>  
>>  #ifdef __has_include
>> -# define __glibc_has_include(header)	__has_include (header)
>> +# define __glibc_has_include __has_include
>>  #else
>>  # define __glibc_has_include(header)	0
>>  #endif
> 
> This is what I plan to commit shortly.
> 
> I don't want to mention the GCC PR in the public header because it will
> be outdated soon (I hope).
> 
> Thanks,
> Florian
> 
> <sys/cdefs.h>: Inhibit macro expansion for __glibc_has_include
> 
> This is currently ineffective with GCC because of GCC PR 80005, but
> it makes sense to anticipate a fix for this defect.
> 
> Suggested by Zack Weinberg.
> 
> 2019-06-14  Florian Weimer  <fweimer@redhat.com>
> 
> 	* misc/sys/cdefs.h (__glibc_has_include): Do not use a
> 	function-like macro, so that __has_include can inhibit expansion
> 	of its argument.
> 

LGTM.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>


> diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
> index 638872b87b..f1bd994a10 100644
> --- a/misc/sys/cdefs.h
> +++ b/misc/sys/cdefs.h
> @@ -413,7 +413,9 @@
>  #endif
>  
>  #ifdef __has_include
> -# define __glibc_has_include(header)	__has_include (header)
> +/* Do not use a function-like macro, so that __has_include can inhibit
> +   macro expansion.  */
> +# define __glibc_has_include __has_include
>  #else
>  # define __glibc_has_include(header)	0
>  #endif
>

Patch
diff mbox series

diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
index 638872b87b..ed146ce20b 100644
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -413,7 +413,7 @@ 
 #endif
 
 #ifdef __has_include
-# define __glibc_has_include(header)	__has_include (header)
+# define __glibc_has_include __has_include
 #else
 # define __glibc_has_include(header)	0
 #endif