Re: [C++ PATCH] Fix option handling when -std=gnu++14 is not used (PR 69865)

[Bernd Edlinger <bernd.edlinger@hotmail.de>]

On 19.02.2016 11:56, Jakub Jelinek wrote:
>
> On Fri, Feb 19, 2016 at 10:50:34AM +0000, Bernd Edlinger wrote:
> > While I think that we should probably not define __GNUC_GNU_INLINE__ at all for C++,
> > because it is meaningless, I am warned that this could break (already broken) header files.
> 
> It is not meaningless.  The various headers need to know if it is safe to
> use the gnu_inline attribute in C++.
> 
> In any case, the desirable state is that e.g. the -E -dD output should be
> identical if you explicitly request the default -std= version vs. if it is
> set implicitly.  We should verify it is the case even for C.
> 
>         Jakub

I absolutely agree with you.
The correct solution is probably doing this:

--- gcc/cp/cfns.h.jj	2016-01-04 15:30:50.000000000 +0100
+++ gcc/cp/cfns.h	2016-02-19 12:00:15.730375049 +0100
@@ -124,9 +124,6 @@
 
 #ifdef __GNUC__
 __inline
-#ifdef __GNUC_STDC_INLINE__
-__attribute__ ((__gnu_inline__))
-#endif
 #endif
 const char *
 libc_name_p (register const char *str, register unsigned int len)

and remove this hunk instead:

@@ -786,7 +790,7 @@ c_common_post_options (const char **pfilename)
   /* By default we use C99 inline semantics in GNU99 or C99 mode.  C99
      inline semantics are not supported in GNU89 or C89 mode.  */
   if (flag_gnu89_inline == -1)
-    flag_gnu89_inline = !flag_isoc99;
+    flag_gnu89_inline = c_dialect_cxx () || !flag_isoc99;
   else if (!flag_gnu89_inline && !flag_isoc99)
     error ("-fno-gnu89-inline is only supported in GNU99 or C99 mode");


Would you like that better?


Thanks
Bernd.