xref: /petsc/src/sys/mpiuni/mpi.c (revision f08646a875d6c8bb0dc8fb3d7c6d74e67952873a)
1 /*
2       This provides a few of the MPI-uni functions that cannot be implemented
3     with C macros
4 */
5 #include <mpiuni/mpi.h>
6 #if !defined(__MPIUNI_H)
7 #error "Wrong mpi.h included! require mpi.h from MPIUNI"
8 #endif
9 #if !defined(PETSC_STDCALL)
10 #define PETSC_STDCALL
11 #endif
12 #include <stdio.h>
13 #if defined(PETSC_HAVE_STDLIB_H)
14 #include <stdlib.h>
15 #endif
16 
17 #define MPI_SUCCESS 0
18 #define MPI_FAILURE 1
19 void    *MPIUNI_TMP        = 0;
20 int     MPIUNI_DATASIZE[10] = {sizeof(int),sizeof(float),sizeof(double),2*sizeof(double),sizeof(char),2*sizeof(int),4*sizeof(double),4,8,2*sizeof(double)};
21 /*
22        With MPI Uni there is only one communicator, which is called 1.
23 */
24 #define MAX_ATTR 128
25 
26 typedef struct {
27   void                *extra_state;
28   void                *attribute_val;
29   int                 active;
30   MPI_Delete_function *del;
31 } MPI_Attr;
32 
33 static MPI_Attr attr[MAX_ATTR];
34 static int      num_attr = 1,mpi_tag_ub = 100000000;
35 
36 #if defined(__cplusplus)
37 extern "C" {
38 #endif
39 
40 /*
41    To avoid problems with prototypes to the system memcpy() it is duplicated here
42 */
43 int MPIUNI_Memcpy(void *a,const void* b,int n) {
44   int  i;
45   char *aa= (char*)a;
46   char *bb= (char*)b;
47 
48   if (b == MPI_IN_PLACE) return 0;
49   for (i=0; i<n; i++) aa[i] = bb[i];
50   return 0;
51 }
52 
53 /*
54    Used to set the built-in MPI_TAG_UB attribute
55 */
56 static int Keyval_setup(void)
57 {
58   attr[0].active        = 1;
59   attr[0].attribute_val = &mpi_tag_ub;
60   return 0;
61 }
62 
63 int MPI_Keyval_create(MPI_Copy_function *copy_fn,MPI_Delete_function *delete_fn,int *keyval,void *extra_state)
64 {
65   if (num_attr >= MAX_ATTR) MPI_Abort(MPI_COMM_WORLD,1);
66 
67   attr[num_attr].extra_state = extra_state;
68   attr[num_attr].del         = delete_fn;
69   *keyval                    = num_attr++;
70   return 0;
71 }
72 
73 int MPI_Keyval_free(int *keyval)
74 {
75   attr[*keyval].active = 0;
76   return MPI_SUCCESS;
77 }
78 
79 int MPI_Attr_put(MPI_Comm comm,int keyval,void *attribute_val)
80 {
81   attr[keyval].active        = 1;
82   attr[keyval].attribute_val = attribute_val;
83   return MPI_SUCCESS;
84 }
85 
86 int MPI_Attr_delete(MPI_Comm comm,int keyval)
87 {
88   if (attr[keyval].active && attr[keyval].del) {
89     void* save_attribute_val   = attr[keyval].attribute_val;
90     attr[keyval].active        = 0;
91     attr[keyval].attribute_val = 0;
92     (*(attr[keyval].del))(comm,keyval,save_attribute_val,attr[keyval].extra_state);
93   }
94   return MPI_SUCCESS;
95 }
96 
97 int MPI_Attr_get(MPI_Comm comm,int keyval,void *attribute_val,int *flag)
98 {
99   if (!keyval) Keyval_setup();
100   *flag                   = attr[keyval].active;
101   *(void **)attribute_val = attr[keyval].attribute_val;
102   return MPI_SUCCESS;
103 }
104 
105 int MPI_Comm_create(MPI_Comm comm,MPI_Group group,MPI_Comm *newcomm)
106 {
107   *newcomm =  comm;
108   return MPI_SUCCESS;
109 }
110 
111 static int dups = 0;
112 int MPI_Comm_dup(MPI_Comm comm,MPI_Comm *out)
113 {
114   *out = comm;
115   dups++;
116   return 0;
117 }
118 
119 int MPI_Comm_free(MPI_Comm *comm)
120 {
121   int i;
122 
123   if (--dups) return MPI_SUCCESS;
124   for (i=0; i<num_attr; i++) {
125     if (attr[i].active && attr[i].del) {
126       (*attr[i].del)(*comm,i,attr[i].attribute_val,attr[i].extra_state);
127     }
128     attr[i].active = 0;
129   }
130   return MPI_SUCCESS;
131 }
132 
133 int MPI_Comm_size(MPI_Comm comm, int*size)
134 {
135   *size=1;
136   return MPI_SUCCESS;
137 }
138 
139 int MPI_Comm_rank(MPI_Comm comm, int*rank)
140 {
141   *rank=0;
142   return MPI_SUCCESS;
143 }
144 
145 int MPI_Abort(MPI_Comm comm,int errorcode)
146 {
147   abort();
148   return MPI_SUCCESS;
149 }
150 
151 /* --------------------------------------------------------------------------*/
152 
153 static int MPI_was_initialized = 0;
154 static int MPI_was_finalized   = 0;
155 
156 int MPI_Init(int *argc, char ***argv)
157 {
158   if (MPI_was_initialized) return 1;
159   if (MPI_was_finalized) return 1;
160   MPI_was_initialized = 1;
161   return 0;
162 }
163 
164 int MPI_Finalize(void)
165 {
166   if (MPI_was_finalized) return 1;
167   if (!MPI_was_initialized) return 1;
168   MPI_was_finalized = 1;
169   return 0;
170 }
171 
172 int MPI_Initialized(int *flag)
173 {
174   *flag = MPI_was_initialized;
175   return 0;
176 }
177 
178 int MPI_Finalized(int *flag)
179 {
180   *flag = MPI_was_finalized;
181   return 0;
182 }
183 
184 /* -------------------     Fortran versions of several routines ------------------ */
185 
186 #if defined(PETSC_HAVE_FORTRAN_CAPS)
187 #define mpi_init_             MPI_INIT
188 #define mpi_finalize_         MPI_FINALIZE
189 #define mpi_comm_size_        MPI_COMM_SIZE
190 #define mpi_comm_rank_        MPI_COMM_RANK
191 #define mpi_abort_            MPI_ABORT
192 #define mpi_reduce_           MPI_REDUCE
193 #define mpi_allreduce_        MPI_ALLREDUCE
194 #define mpi_barrier_          MPI_BARRIER
195 #define mpi_bcast_            MPI_BCAST
196 #define mpi_gather_           MPI_GATHER
197 #define mpi_allgather_        MPI_ALLGATHER
198 #define mpi_comm_split_       MPI_COMM_SPLIT
199 #define mpi_scan_             MPI_SCAN
200 #define mpi_send_             MPI_SEND
201 #define mpi_recv_             MPI_RECV
202 #define mpi_reduce_scatter_   MPI_REDUCE_SCATTER
203 #define mpi_irecv_            MPI_IRECV
204 #define mpi_isend_            MPI_ISEND
205 #define mpi_sendrecv_         MPI_SENDRECV
206 #define mpi_test_             MPI_TEST
207 #define mpi_waitall_          MPI_WAITALL
208 #define mpi_waitany_          MPI_WAITANY
209 #define mpi_allgatherv_       MPI_ALLGATHERV
210 #define mpi_alltoallv_        MPI_ALLTOALLV
211 #define mpi_comm_create_      MPI_COMM_CREATE
212 #define mpi_address_          MPI_ADDRESS
213 #define mpi_pack_             MPI_PACK
214 #define mpi_unpack_           MPI_UNPACK
215 #define mpi_pack_size_        MPI_PACK_SIZE
216 #define mpi_type_struct_      MPI_TYPE_STRUCT
217 #define mpi_type_commit_      MPI_TYPE_COMMIT
218 #define mpi_wtime_            MPI_WTIME
219 #define mpi_cancel_           MPI_CANCEL
220 #define mpi_comm_dup_         MPI_COMM_DUP
221 #define mpi_comm_free_        MPI_COMM_FREE
222 #define mpi_get_count_        MPI_GET_COUNT
223 #define mpi_get_processor_name_ MPI_GET_PROCESSOR_NAME
224 #define mpi_initialized_      MPI_INITIALIZED
225 #define mpi_iprobe_           MPI_IPROBE
226 #define mpi_probe_            MPI_PROBE
227 #define mpi_request_free_     MPI_REQUEST_FREE
228 #define mpi_ssend_            MPI_SSEND
229 #define mpi_wait_             MPI_WAIT
230 #define mpi_comm_group_       MPI_COMM_GROUP
231 #define mpi_exscan_           MPI_EXSCAN
232 #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
233 #define mpi_init_             mpi_init
234 #define mpi_finalize_         mpi_finalize
235 #define mpi_comm_size_        mpi_comm_size
236 #define mpi_comm_rank_        mpi_comm_rank
237 #define mpi_abort_            mpi_abort
238 #define mpi_reduce_           mpi_reduce
239 #define mpi_allreduce_        mpi_allreduce
240 #define mpi_barrier_          mpi_barrier
241 #define mpi_bcast_            mpi_bcast
242 #define mpi_gather_           mpi_gather
243 #define mpi_allgather_        mpi_allgather
244 #define mpi_comm_split_       mpi_comm_split
245 #define mpi_scan_             mpi_scan
246 #define mpi_send_             mpi_send
247 #define mpi_recv_             mpi_recv
248 #define mpi_reduce_scatter_   mpi_reduce_scatter
249 #define mpi_irecv_            mpi_irecv
250 #define mpi_isend_            mpi_isend
251 #define mpi_sendrecv_         mpi_sendrecv
252 #define mpi_test_             mpi_test
253 #define mpi_waitall_          mpi_waitall
254 #define mpi_waitany_          mpi_waitany
255 #define mpi_allgatherv_       mpi_allgatherv
256 #define mpi_alltoallv_        mpi_alltoallv
257 #define mpi_comm_create_      mpi_comm_create
258 #define mpi_address_          mpi_address
259 #define mpi_pack_             mpi_pack
260 #define mpi_unpack_           mpi_unpack
261 #define mpi_pack_size_        mpi_pack_size
262 #define mpi_type_struct_      mpi_type_struct
263 #define mpi_type_commit_      mpi_type_commit
264 #define mpi_wtime_            mpi_wtime
265 #define mpi_cancel_           mpi_cancel
266 #define mpi_comm_dup_         mpi_comm_dup
267 #define mpi_comm_free_        mpi_comm_free
268 #define mpi_get_count_        mpi_get_count
269 #define mpi_get_processor_name_ mpi_get_processor_name
270 #define mpi_initialized_      mpi_initialized
271 #define mpi_iprobe_           mpi_iprobe
272 #define mpi_probe_            mpi_probe
273 #define mpi_request_free_     mpi_request_free
274 #define mpi_ssend_            mpi_ssend
275 #define mpi_wait_             mpi_wait
276 #define mpi_comm_group_       mpi_comm_group
277 #define mpi_exscan_           mpi_exscan
278 #endif
279 
280 #if defined(PETSC_HAVE_FORTRAN_UNDERSCORE_UNDERSCORE)
281 #define mpi_init_             mpi_init__
282 #define mpi_finalize_         mpi_finalize__
283 #define mpi_comm_size_        mpi_comm_size__
284 #define mpi_comm_rank_        mpi_comm_rank__
285 #define mpi_abort_            mpi_abort__
286 #define mpi_reduce_           mpi_reduce__
287 #define mpi_allreduce_        mpi_allreduce__
288 #define mpi_barrier_          mpi_barrier__
289 #define mpi_bcast_            mpi_bcast__
290 #define mpi_gather_           mpi_gather__
291 #define mpi_allgather_        mpi_allgather__
292 #define mpi_comm_split_       mpi_comm_split__
293 #define mpi_scan_             mpi_scan__
294 #define mpi_send_             mpi_send__
295 #define mpi_recv_             mpi_recv__
296 #define mpi_reduce_scatter_   mpi_reduce_scatter__
297 #define mpi_irecv_            mpi_irecv__
298 #define mpi_isend_            mpi_isend__
299 #define mpi_sendrecv_         mpi_sendrecv__
300 #define mpi_test_             mpi_test__
301 #define mpi_waitall_          mpi_waitall__
302 #define mpi_waitany_          mpi_waitany__
303 #define mpi_allgatherv_       mpi_allgatherv__
304 #define mpi_alltoallv_        mpi_alltoallv__
305 #define mpi_comm_create_      mpi_comm_create__
306 #define mpi_address_          mpi_address__
307 #define mpi_pack_             mpi_pack__
308 #define mpi_unpack_           mpi_unpack__
309 #define mpi_pack_size_        mpi_pack_size__
310 #define mpi_type_struct_      mpi_type_struct__
311 #define mpi_type_commit_      mpi_type_commit__
312 #define mpi_wtime_            mpi_wtime__
313 #define mpi_cancel_           mpi_cancel__
314 #define mpi_comm_dup_         mpi_comm_dup__
315 #define mpi_comm_free_        mpi_comm_free__
316 #define mpi_get_count_        mpi_get_count__
317 #define mpi_get_processor_name_ mpi_get_processor_name__
318 #define mpi_initialized_      mpi_initialized__
319 #define mpi_iprobe_           mpi_iprobe__
320 #define mpi_probe_            mpi_probe__
321 #define mpi_request_free_     mpi_request_free__
322 #define mpi_ssend_            mpi_ssend__
323 #define mpi_wait_             mpi_wait__
324 #define mpi_comm_group_       mpi_comm_group__
325 #define mpi_exscan_           mpi_exscan__
326 #endif
327 
328 
329 /* Do not build fortran interface if MPI namespace colision is to be avoided */
330 #if !defined(MPIUNI_AVOID_MPI_NAMESPACE)
331 
332 void PETSC_STDCALL  mpi_init_(int *ierr)
333 {
334   *ierr = MPI_Init((int*)0, (char***)0);
335 }
336 
337 void PETSC_STDCALL  mpi_finalize_(int *ierr)
338 {
339   *ierr = MPI_Finalize();
340 }
341 
342 void PETSC_STDCALL mpi_comm_size_(MPI_Comm *comm,int *size,int *ierr)
343 {
344   *size = 1;
345   *ierr = 0;
346 }
347 
348 void PETSC_STDCALL mpi_comm_rank_(MPI_Comm *comm,int *rank,int *ierr)
349 {
350   *rank=0;
351   *ierr=MPI_SUCCESS;
352 }
353 
354 void PETSC_STDCALL mpi_comm_split_(MPI_Comm *comm,int *color,int *key, MPI_Comm *newcomm, int *ierr)
355 {
356   *newcomm = *comm;
357   *ierr=MPI_SUCCESS;
358 }
359 
360 void PETSC_STDCALL mpi_abort_(MPI_Comm *comm,int *errorcode,int *ierr)
361 {
362   abort();
363   *ierr = MPI_SUCCESS;
364 }
365 
366 void PETSC_STDCALL mpi_reduce_(void *sendbuf,void *recvbuf,int *count,int *datatype,int *op,int *root,int *comm,int *ierr)
367 {
368   MPIUNI_Memcpy(recvbuf,sendbuf,(*count)*MPIUNI_DATASIZE[*datatype]);
369   *ierr = MPI_SUCCESS;
370 }
371 
372 void PETSC_STDCALL mpi_allreduce_(void *sendbuf,void *recvbuf,int *count,int *datatype,int *op,int *comm,int *ierr)
373 {
374   MPIUNI_Memcpy(recvbuf,sendbuf,(*count)*MPIUNI_DATASIZE[*datatype]);
375   *ierr = MPI_SUCCESS;
376 }
377 
378 void PETSC_STDCALL mpi_barrier_(MPI_Comm *comm,int *ierr)
379 {
380   *ierr = MPI_SUCCESS;
381 }
382 
383 void PETSC_STDCALL mpi_bcast_(void *buf,int *count,int *datatype,int *root,int *comm,int *ierr)
384 {
385   *ierr = MPI_SUCCESS;
386 }
387 
388 
389 void PETSC_STDCALL mpi_gather_(void *sendbuf,int *scount,int *sdatatype, void* recvbuf, int* rcount, int* rdatatype, int *root,int *comm,int *ierr)
390 {
391   MPIUNI_Memcpy(recvbuf,sendbuf,(*scount)*MPIUNI_DATASIZE[*sdatatype]);
392   *ierr = MPI_SUCCESS;
393 }
394 
395 void PETSC_STDCALL mpi_allgather_(void *sendbuf,int *scount,int *sdatatype, void* recvbuf, int* rcount, int* rdatatype,int *comm,int *ierr)
396 {
397   MPIUNI_Memcpy(recvbuf,sendbuf,(*scount)*MPIUNI_DATASIZE[*sdatatype]);
398   *ierr = MPI_SUCCESS;
399 }
400 
401 void PETSC_STDCALL mpi_scan_(void *sendbuf,void *recvbuf,int *count,int *datatype,int *op,int *comm,int *ierr)
402 {
403   MPIUNI_Memcpy(recvbuf,sendbuf,(*count)*MPIUNI_DATASIZE[*datatype]);
404   *ierr = MPI_SUCCESS;
405 }
406 
407 void PETSC_STDCALL mpi_send_(void*buf,int *count,int *datatype,int *dest,int *tag,int *comm,int *ierr )
408 {
409   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
410 }
411 
412 void PETSC_STDCALL mpi_recv_(void*buf,int *count,int *datatype,int *source,int *tag,int *comm,int status,int *ierr )
413 {
414   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
415 }
416 
417 void PETSC_STDCALL mpi_reduce_scatter_(void*sendbuf,void*recvbuf,int *recvcounts,int *datatype,int *op,int *comm,int *ierr)
418 {
419   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
420 }
421 
422 void PETSC_STDCALL mpi_irecv_(void*buf,int *count, int *datatype, int *source, int *tag, int *comm, int *request, int *ierr)
423 {
424   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
425 }
426 
427 void PETSC_STDCALL mpi_isend_(void*buf,int *count,int *datatype,int *dest,int *tag,int *comm,int *request, int *ierr)
428 {
429   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
430 }
431 
432 void PETSC_STDCALL mpi_sendrecv_(void*sendbuf,int *sendcount,int *sendtype,int *dest,int *sendtag,void*recvbuf,int *recvcount,int *recvtype,int *source,int *recvtag,int *comm,int *status,int *ierr)
433 {
434   MPIUNI_Memcpy(recvbuf,sendbuf,(*sendcount)*MPIUNI_DATASIZE[*sendtype]);
435   *ierr = MPI_SUCCESS;
436 }
437 
438 void PETSC_STDCALL mpi_test_(int *request,int *flag,int *status,int *ierr)
439 {
440   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
441 }
442 
443 void PETSC_STDCALL mpi_waitall_(int *count,int *array_of_requests,int *array_of_statuses,int *ierr)
444 {
445   *ierr = MPI_SUCCESS;
446 }
447 
448   void PETSC_STDCALL mpi_waitany_(int *count,int *array_of_requests,int * index, int *status,int *ierr)
449 {
450   *ierr = MPI_SUCCESS;
451 }
452 
453 void PETSC_STDCALL mpi_allgatherv_(void*sendbuf,int *sendcount,int *sendtype,void*recvbuf,int *recvcounts,int *displs,int *recvtype,int *comm,int *ierr)
454 {
455   MPIUNI_Memcpy(recvbuf,sendbuf,(*sendcount)*MPIUNI_DATASIZE[*sendtype]);
456   *ierr = MPI_SUCCESS;
457 }
458 
459 void PETSC_STDCALL mpi_alltoallv_(void*sendbuf,int *sendcounts,int *sdispls,int *sendtype,void*recvbuf,int *recvcounts,int *rdispls,int *recvtype,int *comm,int *ierr)
460 {
461   MPIUNI_Memcpy(recvbuf,sendbuf,(*sendcounts)*MPIUNI_DATASIZE[*sendtype]);
462   *ierr = MPI_SUCCESS;
463 }
464 
465 void PETSC_STDCALL mpi_comm_create_(int *comm,int *group,int *newcomm,int *ierr)
466 {
467   *newcomm =  *comm;
468   *ierr = MPI_SUCCESS;
469 }
470 
471 void PETSC_STDCALL mpi_address_(void*location,MPIUNI_INTPTR *address,int *ierr)
472 {
473   *address =  (MPIUNI_INTPTR) location;
474   *ierr = MPI_SUCCESS;
475 }
476 
477 void PETSC_STDCALL mpi_pack_(void*inbuf,int *incount,int *datatype,void*outbuf,int *outsize,int *position,int *comm,int *ierr)
478 {
479   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
480 }
481 
482 void PETSC_STDCALL mpi_unpack_(void*inbuf,int *insize,int *position,void*outbuf,int *outcount,int *datatype,int *comm,int *ierr)
483 {
484   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
485 }
486 
487 void PETSC_STDCALL mpi_pack_size_(int *incount,int *datatype,int *comm,int *size,int *ierr)
488 {
489   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
490 }
491 
492 void PETSC_STDCALL mpi_type_struct_(int *count,int *array_of_blocklengths,int * array_of_displaments,int *array_of_types,int *newtype,int *ierr)
493 {
494   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
495 }
496 
497 void PETSC_STDCALL mpi_type_commit_(int *datatype,int *ierr)
498 {
499   *ierr = MPI_SUCCESS;
500 }
501 
502 double PETSC_STDCALL mpi_wtime_(void)
503 {
504   return 0.0;
505 }
506 
507 void PETSC_STDCALL mpi_cancel_(int *request,int *ierr)
508 {
509   *ierr = MPI_SUCCESS;
510 }
511 
512 void PETSC_STDCALL mpi_comm_dup_(int *comm,int *out,int *ierr)
513 {
514   *out = *comm;
515   *ierr = MPI_SUCCESS;
516 }
517 
518 void PETSC_STDCALL mpi_comm_free_(int *comm,int *ierr)
519 {
520   *ierr = MPI_SUCCESS;
521 }
522 
523 void PETSC_STDCALL mpi_get_count_(int *status,int *datatype,int *count,int *ierr)
524 {
525   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
526 }
527 
528 /* duplicate from fortranimpl.h */
529 #if defined(PETSC_HAVE_FORTRAN_MIXED_STR_ARG)
530 #define PETSC_MIXED_LEN(len) ,int len
531 #define PETSC_END_LEN(len)
532 #else
533 #define PETSC_MIXED_LEN(len)
534 #define PETSC_END_LEN(len)   ,int len
535 #endif
536 
537 void PETSC_STDCALL mpi_get_processor_name_(char *name PETSC_MIXED_LEN(len),int *result_len,int *ierr PETSC_END_LEN(len))
538 {
539   MPIUNI_Memcpy(name,"localhost",9*sizeof(char));
540   *result_len = 9;
541   *ierr = MPI_SUCCESS;
542 }
543 
544 void PETSC_STDCALL mpi_initialized_(int *flag,int *ierr)
545 {
546   *flag = MPI_was_initialized;
547   *ierr = MPI_SUCCESS;
548 }
549 
550 void PETSC_STDCALL mpi_iprobe_(int *source,int *tag,int *comm,int *glag,int *status,int *ierr)
551 {
552   *ierr = MPI_SUCCESS;
553 }
554 
555 void PETSC_STDCALL mpi_probe_(int *source,int *tag,int *comm,int *flag,int *status,int *ierr)
556 {
557   *ierr = MPI_SUCCESS;
558 }
559 
560 void PETSC_STDCALL mpi_request_free_(int *request,int *ierr)
561 {
562   *ierr = MPI_SUCCESS;
563 }
564 
565 void PETSC_STDCALL mpi_ssend_(void*buf,int *count,int *datatype,int *dest,int *tag,int *comm,int *ierr)
566 {
567   *ierr = MPI_Abort(MPI_COMM_WORLD,0);
568 }
569 
570 void PETSC_STDCALL mpi_wait_(int *request,int *status,int *ierr)
571 {
572   *ierr = MPI_SUCCESS;
573 }
574 
575 void PETSC_STDCALL mpi_comm_group_(int*comm,int*group,int *ierr)
576 {
577   *ierr = MPI_SUCCESS;
578 }
579 
580 void PETSC_STDCALL mpi_exscan_(void*sendbuf,void*recvbuf,int*count,int*datatype,int*op,int*comm,int*ierr)
581 {
582   *ierr = MPI_SUCCESS;
583 }
584 
585 #endif /* MPIUNI_AVOID_MPI_NAMESPACE */
586 
587 #if defined(__cplusplus)
588 }
589 #endif
590