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Re: restore bootstrap with a C++ compiler
Gabriel Dos Reis <gdr@cs.tamu.edu> writes:
> Andrew Pinski <pinskia@gmail.com> writes:
>
> | On Wed, Apr 27, 2011 at 6:48 PM, Gabriel Dos Reis <gdr@cs.tamu.edu> wrote:
> | > A local `extern' declaration does not give the entity an external linkage
> | > -- irrespective of the linkage of the function enclosing the declaration.
> | > It just makes the name locally available for name lookup
> | > purpose. Â A variable declared const has
> | > Â-- external linkage by default in C
> | > Â-- internal linkage by default in C++
> | >
> | > So before the patch: the variables had external linkage in C, but
> | > internal linkage in C++. ÂThat meant that a link will fail in C++, but
> | > succeeds in C. ÂAll my patch did was to give the external linkage
> | > explicitly (both in C and in C++.)
> |
> | Then I think a better fix is to do:
> | Index: internal-fn.c
> | ===================================================================
> | --- internal-fn.c (revision 172940)
> | +++ internal-fn.c (working copy)
> | @@ -27,6 +27,7 @@ along with GCC; see the file COPYING3.
> | #include "gimple.h"
> |
> | /* The names of each internal function, indexed by function number. */
> | +extern const char *const internal_fn_name_array[];
> | const char *const internal_fn_name_array[] = {
> | #define DEF_INTERNAL_FN(CODE, FLAGS) #CODE,
> | #include "internal-fn.def"
> | @@ -35,6 +36,7 @@ const char *const internal_fn_name_array
> | };
> |
> | /* The ECF_* flags of each internal function, indexed by function number. */
> | +extern const int internal_fn_flags_array[];
> | const int internal_fn_flags_array[] = {
> | #define DEF_INTERNAL_FN(CODE, FLAGS) FLAGS,
> | #include "internal-fn.def"
> | --- CUT ---
> | So nobody is tempted to use those arrays directly from the code but
> | rather only use the static inline functions.
>
> Well, anybody who can put those extern declarations anywhere and use
> them directly. The real issue is that the array variables have external
> linkage.
>
> So, I think the patch is largely stylistic but equivalent; I'll defer to
> you which one should "prevail".
FWIW, I prefer Andrew's patch, but since yours has been applied,
I suppose there's no point changing it.
Richard