RFC: Fix plugins/44459 2/2

This is the second part of the patch set to fix PR44459, which adds
extern "C" linkage to a few very common functions that are used in
the plugin tests of the gcc testsuite.
If more, or less, or any of these should be included, might be subject to
debate.

Bootstrapped and regression tested in 160389 with --enable-build-with-cxx

Together with the first part, in addition to
testsuite/gcc.dg/plugin/one_time_plugin.c , this patch set allows
testsuite/gcc.dg/plugin/ggcplug.c and testsuite/gcc.dg/plugin/dumb_plugin.c
to be compiled with gcc into a functioning gcc plugin.
2010-06-08  Joern Rennecke  <joern.rennecke@embecosm.com>

	PR plugins/44459:
	* tree.h: Encapsulate declarations for tree accessor failure functions
	in extern "C".
	* diagnostic-core.h (warning): Encapsulate declaration in extern "C".
	* system.h (fancy_abort): Encapsulate declaration in extern "C".

On Tue, Jun 8, 2010 at 2:36 PM, Joern Rennecke <amylaar@spamcop.net> wrote:
> This is the second part of the patch set to fix PR44459, which adds
> extern "C" linkage to a few very common functions that are used in
> the plugin tests of the gcc testsuite.
> If more, or less, or any of these should be included, might be subject to
> debate.
>
> Bootstrapped and regression tested in 160389 with --enable-build-with-cxx
>
> Together with the first part, in addition to
> testsuite/gcc.dg/plugin/one_time_plugin.c , this patch set allows
> testsuite/gcc.dg/plugin/ggcplug.c and testsuite/gcc.dg/plugin/dumb_plugin.c
> to be compiled with gcc into a functioning gcc plugin.

Sorry - I do not think that this is the way to go.

Richard.

>
> 2010-06-08  Joern Rennecke  <joern.rennecke@embecosm.com>
>
>        PR plugins/44459:
>        * tree.h: Encapsulate declarations for tree accessor failure
> functions
>        in extern "C".
>        * diagnostic-core.h (warning): Encapsulate declaration in extern "C".
>        * system.h (fancy_abort): Encapsulate declaration in extern "C".
>
> Index: tree.h
> ===================================================================
> --- tree.h      (revision 160389)
> +++ tree.h      (working copy)
> @@ -871,6 +871,10 @@ enum tree_node_structure_enum {
>  (*({__typeof (NODE) const __t = (NODE);
>    \
>     &__t->common.type; }))
>
> +/* Make accessor macros usable in plugins compiled as C.  */
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
>  extern void tree_contains_struct_check_failed (const_tree,
>                                               const enum
> tree_node_structure_enum,
>                                               const char *, int, const char
> *)
> @@ -910,6 +914,9 @@ extern void omp_clause_range_check_faile
>                               const char *, enum omp_clause_code,
>                               enum omp_clause_code)
>     ATTRIBUTE_NORETURN;
> +#ifdef __cplusplus
> +}
> +#endif
>
>  #else /* not ENABLE_TREE_CHECKING, or not gcc */
>
> Index: diagnostic-core.h
> ===================================================================
> --- diagnostic-core.h   (revision 160389)
> +++ diagnostic-core.h   (working copy)
> @@ -55,7 +55,14 @@ extern const char *trim_filename (const
>  extern void internal_error (const char *, ...) ATTRIBUTE_GCC_DIAG(1,2)
>      ATTRIBUTE_NORETURN;
>  /* Pass one of the OPT_W* from options.h as the first parameter.  */
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +/* C linkage so that plugins can use it more easyly.  */
>  extern bool warning (int, const char *, ...) ATTRIBUTE_GCC_DIAG(2,3);
> +#ifdef __cplusplus
> +}
> +#endif
>  extern bool warning_at (location_t, int, const char *, ...)
>     ATTRIBUTE_GCC_DIAG(3,4);
>  extern void error (const char *, ...) ATTRIBUTE_GCC_DIAG(1,2);
> Index: system.h
> ===================================================================
> --- system.h    (revision 160389)
> +++ system.h    (working copy)
> @@ -586,7 +586,14 @@ extern int vsnprintf(char *, size_t, con
>
>  /* Redefine abort to report an internal error w/o coredump, and
>    reporting the location of the error in the source file.  */
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +/* C linkage so that it can be used more easily by plugins.  */
>  extern void fancy_abort (const char *, int, const char *)
> ATTRIBUTE_NORETURN;
> +#ifdef __cplusplus
> +}
> +#endif
>  #define abort() fancy_abort (__FILE__, __LINE__, __FUNCTION__)
>
>  /* Use gcc_assert(EXPR) to test invariants.  */
>
>