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Use FLEXIBLE_ARRAY_MEMBER in a bunch more places.
Replace some bogus "x[1]" declarations with "x[FLEXIBLE_ARRAY_MEMBER]". Aside from being more self-documenting, this should help prevent bogus warnings from static code analyzers and perhaps compiler misoptimizations. This patch is just a down payment on eliminating the whole problem, but it gets rid of a lot of easy-to-fix cases. Note that the main problem with doing this is that one must no longer rely on computing sizeof(the containing struct), since the result would be compiler-dependent. Instead use offsetof(struct, lastfield). Autoconf also warns against spelling that offsetof(struct, lastfield[0]). Michael Paquier, review and additional fixes by me.
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44 files changed

+109
-127
lines changed

‎contrib/cube/cubedata.h

Lines changed: 7 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -23,11 +23,10 @@ typedef struct NDBOX
2323
unsigned int header;
2424

2525
/*
26-
* Variable length array. The lower left coordinates for each dimension
27-
* come first, followed by upper right coordinates unless the point flag
28-
* is set.
26+
* The lower left coordinates for each dimension come first, followed by
27+
* upper right coordinates unless the point flag is set.
2928
*/
30-
double x[1];
29+
double x[FLEXIBLE_ARRAY_MEMBER];
3130
} NDBOX;
3231

3332
#define POINT_BIT 0x80000000
@@ -41,9 +40,9 @@ typedef struct NDBOX
4140
#define LL_COORD(cube, i) ( (cube)->x[i] )
4241
#define UR_COORD(cube, i) ( IS_POINT(cube) ? (cube)->x[i] : (cube)->x[(i) + DIM(cube)] )
4342

44-
#define POINT_SIZE(_dim) (offsetof(NDBOX, x[0]) + sizeof(double)*(_dim))
45-
#define CUBE_SIZE(_dim) (offsetof(NDBOX, x[0]) + sizeof(double)*(_dim)*2)
43+
#define POINT_SIZE(_dim) (offsetof(NDBOX, x) + sizeof(double)*(_dim))
44+
#define CUBE_SIZE(_dim) (offsetof(NDBOX, x) + sizeof(double)*(_dim)*2)
4645

47-
#define DatumGetNDBOX(x) ((NDBOX*)DatumGetPointer(x))
48-
#define PG_GETARG_NDBOX(x) DatumGetNDBOX( PG_DETOAST_DATUM(PG_GETARG_DATUM(x)) )
46+
#define DatumGetNDBOX(x) ((NDBOX *) PG_DETOAST_DATUM(x))
47+
#define PG_GETARG_NDBOX(x) DatumGetNDBOX(PG_GETARG_DATUM(x))
4948
#define PG_RETURN_NDBOX(x) PG_RETURN_POINTER(x)

‎contrib/intarray/_int.h

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -73,7 +73,7 @@ typedef struct
7373
{
7474
int32 vl_len_; /* varlena header (do not touch directly!) */
7575
int32 flag;
76-
char data[1];
76+
char data[FLEXIBLE_ARRAY_MEMBER];
7777
} GISTTYPE;
7878

7979
#define ALLISTRUE 0x04
@@ -133,7 +133,7 @@ typedef struct QUERYTYPE
133133
{
134134
int32 vl_len_; /* varlena header (do not touch directly!) */
135135
int32 size; /* number of ITEMs */
136-
ITEM items[1]; /* variable length array */
136+
ITEM items[FLEXIBLE_ARRAY_MEMBER];
137137
} QUERYTYPE;
138138

139139
#define HDRSIZEQT offsetof(QUERYTYPE, items)

‎contrib/ltree/ltree.h

Lines changed: 7 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -10,7 +10,7 @@
1010
typedef struct
1111
{
1212
uint16 len;
13-
char name[1];
13+
char name[FLEXIBLE_ARRAY_MEMBER];
1414
} ltree_level;
1515

1616
#define LEVEL_HDRSIZE (offsetof(ltree_level,name))
@@ -20,7 +20,7 @@ typedef struct
2020
{
2121
int32 vl_len_; /* varlena header (do not touch directly!) */
2222
uint16 numlevel;
23-
char data[1];
23+
char data[FLEXIBLE_ARRAY_MEMBER];
2424
} ltree;
2525

2626
#define LTREE_HDRSIZE MAXALIGN( offsetof(ltree, data) )
@@ -34,7 +34,7 @@ typedef struct
3434
int32 val;
3535
uint16 len;
3636
uint8 flag;
37-
char name[1];
37+
char name[FLEXIBLE_ARRAY_MEMBER];
3838
} lquery_variant;
3939

4040
#define LVAR_HDRSIZE MAXALIGN(offsetof(lquery_variant, name))
@@ -51,7 +51,7 @@ typedef struct
5151
uint16 numvar;
5252
uint16 low;
5353
uint16 high;
54-
char variants[1];
54+
char variants[FLEXIBLE_ARRAY_MEMBER];
5555
} lquery_level;
5656

5757
#define LQL_HDRSIZE MAXALIGN( offsetof(lquery_level,variants) )
@@ -72,7 +72,7 @@ typedef struct
7272
uint16 numlevel;
7373
uint16 firstgood;
7474
uint16 flag;
75-
char data[1];
75+
char data[FLEXIBLE_ARRAY_MEMBER];
7676
} lquery;
7777

7878
#define LQUERY_HDRSIZE MAXALIGN( offsetof(lquery, data) )
@@ -107,7 +107,7 @@ typedef struct
107107
{
108108
int32 vl_len_; /* varlena header (do not touch directly!) */
109109
int32 size;
110-
char data[1];
110+
char data[FLEXIBLE_ARRAY_MEMBER];
111111
} ltxtquery;
112112

113113
#define HDRSIZEQT MAXALIGN(VARHDRSZ + sizeof(int32))
@@ -208,7 +208,7 @@ typedef struct
208208
{
209209
int32 vl_len_; /* varlena header (do not touch directly!) */
210210
uint32 flag;
211-
char data[1];
211+
char data[FLEXIBLE_ARRAY_MEMBER];
212212
} ltree_gist;
213213

214214
#define LTG_ONENODE 0x01

‎contrib/pageinspect/rawpage.c

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -192,7 +192,7 @@ page_header(PG_FUNCTION_ARGS)
192192
* Check that enough data was supplied, so that we don't try to access
193193
* fields outside the supplied buffer.
194194
*/
195-
if (raw_page_size < sizeof(PageHeaderData))
195+
if (raw_page_size < SizeOfPageHeaderData)
196196
ereport(ERROR,
197197
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
198198
errmsg("input page too small (%d bytes)", raw_page_size)));

‎contrib/pg_trgm/trgm.h

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -63,7 +63,7 @@ typedef struct
6363
{
6464
int32 vl_len_; /* varlena header (do not touch directly!) */
6565
uint8 flag;
66-
char data[1];
66+
char data[FLEXIBLE_ARRAY_MEMBER];
6767
} TRGM;
6868

6969
#define TRGMHDRSIZE (VARHDRSZ + sizeof(uint8))

‎src/backend/catalog/namespace.c

Lines changed: 7 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -261,9 +261,9 @@ RangeVarGetRelidExtended(const RangeVar *relation, LOCKMODE lockmode,
261261
* with the answer changing under them, or that they already hold some
262262
* appropriate lock, and therefore return the first answer we get without
263263
* checking for invalidation messages. Also, if the requested lock is
264-
* already held, LockRelationOid will not AcceptInvalidationMessages,
265-
* so we may fail to notice a change. We could protect against that case
266-
* by calling AcceptInvalidationMessages() before beginning this loop, but
264+
* already held, LockRelationOid will not AcceptInvalidationMessages, so
265+
* we may fail to notice a change. We could protect against that case by
266+
* calling AcceptInvalidationMessages() before beginning this loop, but
267267
* that would add a significant amount overhead, so for now we don't.
268268
*/
269269
for (;;)
@@ -1075,8 +1075,8 @@ FuncnameGetCandidates(List *names, int nargs, List *argnames,
10751075
*/
10761076
effective_nargs = Max(pronargs, nargs);
10771077
newResult = (FuncCandidateList)
1078-
palloc(sizeof(struct _FuncCandidateList) - sizeof(Oid)
1079-
+ effective_nargs * sizeof(Oid));
1078+
palloc(offsetof(struct _FuncCandidateList, args) +
1079+
effective_nargs * sizeof(Oid));
10801080
newResult->pathpos = pathpos;
10811081
newResult->oid = HeapTupleGetOid(proctup);
10821082
newResult->nargs = effective_nargs;
@@ -1597,7 +1597,8 @@ OpernameGetCandidates(List *names, char oprkind, bool missing_schema_ok)
15971597
* separate palloc for each operator, but profiling revealed that the
15981598
* pallocs used an unreasonably large fraction of parsing time.
15991599
*/
1600-
#define SPACE_PER_OP MAXALIGN(sizeof(struct _FuncCandidateList) + sizeof(Oid))
1600+
#define SPACE_PER_OP MAXALIGN(offsetof(struct _FuncCandidateList, args) + \
1601+
2 * sizeof(Oid))
16011602

16021603
if (catlist->n_members > 0)
16031604
resultSpace = palloc(catlist->n_members * SPACE_PER_OP);

‎src/backend/commands/prepare.c

Lines changed: 2 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -383,10 +383,9 @@ EvaluateParams(PreparedStatement *pstmt, List *params,
383383
/* Prepare the expressions for execution */
384384
exprstates = (List *) ExecPrepareExpr((Expr *) params, estate);
385385

386-
/* sizeof(ParamListInfoData) includes the first array element */
387386
paramLI = (ParamListInfo)
388-
palloc(sizeof(ParamListInfoData) +
389-
(num_params - 1) * sizeof(ParamExternData));
387+
palloc(offsetof(ParamListInfoData, params) +
388+
num_params * sizeof(ParamExternData));
390389
/* we have static list of params, so no hooks needed */
391390
paramLI->paramFetch = NULL;
392391
paramLI->paramFetchArg = NULL;

‎src/backend/executor/functions.c

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -896,9 +896,9 @@ postquel_sub_params(SQLFunctionCachePtr fcache,
896896

897897
if (fcache->paramLI == NULL)
898898
{
899-
/* sizeof(ParamListInfoData) includes the first array element */
900-
paramLI = (ParamListInfo) palloc(sizeof(ParamListInfoData) +
901-
(nargs - 1) * sizeof(ParamExternData));
899+
paramLI = (ParamListInfo)
900+
palloc(offsetof(ParamListInfoData, params) +
901+
nargs * sizeof(ParamExternData));
902902
/* we have static list of params, so no hooks needed */
903903
paramLI->paramFetch = NULL;
904904
paramLI->paramFetchArg = NULL;

‎src/backend/executor/spi.c

Lines changed: 2 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -2290,9 +2290,8 @@ _SPI_convert_params(int nargs, Oid *argtypes,
22902290
{
22912291
int i;
22922292

2293-
/* sizeof(ParamListInfoData) includes the first array element */
2294-
paramLI = (ParamListInfo) palloc(sizeof(ParamListInfoData) +
2295-
(nargs - 1) * sizeof(ParamExternData));
2293+
paramLI = (ParamListInfo) palloc(offsetof(ParamListInfoData, params) +
2294+
nargs * sizeof(ParamExternData));
22962295
/* we have static list of params, so no hooks needed */
22972296
paramLI->paramFetch = NULL;
22982297
paramLI->paramFetchArg = NULL;

‎src/backend/nodes/params.c

Lines changed: 2 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -40,9 +40,8 @@ copyParamList(ParamListInfo from)
4040
if (from == NULL || from->numParams <= 0)
4141
return NULL;
4242

43-
/* sizeof(ParamListInfoData) includes the first array element */
44-
size = sizeof(ParamListInfoData) +
45-
(from->numParams - 1) * sizeof(ParamExternData);
43+
size = offsetof(ParamListInfoData, params) +
44+
from->numParams * sizeof(ParamExternData);
4645

4746
retval = (ParamListInfo) palloc(size);
4847
retval->paramFetch = NULL;

‎src/backend/postmaster/syslogger.c

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -785,13 +785,13 @@ process_pipe_input(char *logbuffer, int *bytes_in_logbuffer)
785785
int dest = LOG_DESTINATION_STDERR;
786786

787787
/* While we have enough for a header, process data... */
788-
while (count >= (int) sizeof(PipeProtoHeader))
788+
while (count >= (int) (offsetof(PipeProtoHeader, data) +1))
789789
{
790790
PipeProtoHeader p;
791791
int chunklen;
792792

793793
/* Do we have a valid header? */
794-
memcpy(&p, cursor, sizeof(PipeProtoHeader));
794+
memcpy(&p, cursor, offsetof(PipeProtoHeader, data));
795795
if (p.nuls[0] == '\0' && p.nuls[1] == '\0' &&
796796
p.len > 0 && p.len <= PIPE_MAX_PAYLOAD &&
797797
p.pid != 0 &&

‎src/backend/tcop/postgres.c

Lines changed: 2 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -1619,9 +1619,8 @@ exec_bind_message(StringInfo input_message)
16191619
{
16201620
int paramno;
16211621

1622-
/* sizeof(ParamListInfoData) includes the first array element */
1623-
params = (ParamListInfo) palloc(sizeof(ParamListInfoData) +
1624-
(numParams - 1) * sizeof(ParamExternData));
1622+
params = (ParamListInfo) palloc(offsetof(ParamListInfoData, params) +
1623+
numParams * sizeof(ParamExternData));
16251624
/* we have static list of params, so no hooks needed */
16261625
params->paramFetch = NULL;
16271626
params->paramFetchArg = NULL;

‎src/backend/utils/adt/geo_ops.c

Lines changed: 11 additions & 11 deletions
Original file line numberDiff line numberDiff line change
@@ -1390,7 +1390,7 @@ path_in(PG_FUNCTION_ARGS)
13901390
}
13911391

13921392
base_size = sizeof(path->p[0]) * npts;
1393-
size = offsetof(PATH, p[0]) +base_size;
1393+
size = offsetof(PATH, p) +base_size;
13941394

13951395
/* Check for integer overflow */
13961396
if (base_size / npts != sizeof(path->p[0]) || size <= base_size)
@@ -1443,12 +1443,12 @@ path_recv(PG_FUNCTION_ARGS)
14431443

14441444
closed = pq_getmsgbyte(buf);
14451445
npts = pq_getmsgint(buf, sizeof(int32));
1446-
if (npts <= 0 || npts >= (int32) ((INT_MAX - offsetof(PATH, p[0])) / sizeof(Point)))
1446+
if (npts <= 0 || npts >= (int32) ((INT_MAX - offsetof(PATH, p)) / sizeof(Point)))
14471447
ereport(ERROR,
14481448
(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
14491449
errmsg("invalid number of points in external \"path\" value")));
14501450

1451-
size = offsetof(PATH, p[0]) +sizeof(path->p[0]) * npts;
1451+
size = offsetof(PATH, p) +sizeof(path->p[0]) * npts;
14521452
path = (PATH *) palloc(size);
14531453

14541454
SET_VARSIZE(path, size);
@@ -3476,7 +3476,7 @@ poly_in(PG_FUNCTION_ARGS)
34763476
errmsg("invalid input syntax for type polygon: \"%s\"", str)));
34773477

34783478
base_size = sizeof(poly->p[0]) * npts;
3479-
size = offsetof(POLYGON, p[0]) +base_size;
3479+
size = offsetof(POLYGON, p) +base_size;
34803480

34813481
/* Check for integer overflow */
34823482
if (base_size / npts != sizeof(poly->p[0]) || size <= base_size)
@@ -3530,12 +3530,12 @@ poly_recv(PG_FUNCTION_ARGS)
35303530
int size;
35313531

35323532
npts = pq_getmsgint(buf, sizeof(int32));
3533-
if (npts <= 0 || npts >= (int32) ((INT_MAX - offsetof(POLYGON, p[0])) / sizeof(Point)))
3533+
if (npts <= 0 || npts >= (int32) ((INT_MAX - offsetof(POLYGON, p)) / sizeof(Point)))
35343534
ereport(ERROR,
35353535
(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
35363536
errmsg("invalid number of points in external \"polygon\" value")));
35373537

3538-
size = offsetof(POLYGON, p[0]) +sizeof(poly->p[0]) * npts;
3538+
size = offsetof(POLYGON, p) +sizeof(poly->p[0]) * npts;
35393539
poly = (POLYGON *) palloc0(size); /* zero any holes */
35403540

35413541
SET_VARSIZE(poly, size);
@@ -4251,7 +4251,7 @@ path_add(PG_FUNCTION_ARGS)
42514251
PG_RETURN_NULL();
42524252

42534253
base_size = sizeof(p1->p[0]) * (p1->npts + p2->npts);
4254-
size = offsetof(PATH, p[0]) +base_size;
4254+
size = offsetof(PATH, p) +base_size;
42554255

42564256
/* Check for integer overflow */
42574257
if (base_size / sizeof(p1->p[0]) != (p1->npts + p2->npts) ||
@@ -4393,7 +4393,7 @@ path_poly(PG_FUNCTION_ARGS)
43934393
* Never overflows: the old size fit in MaxAllocSize, and the new size is
43944394
* just a small constant larger.
43954395
*/
4396-
size = offsetof(POLYGON, p[0]) +sizeof(poly->p[0]) * path->npts;
4396+
size = offsetof(POLYGON, p) +sizeof(poly->p[0]) * path->npts;
43974397
poly = (POLYGON *) palloc(size);
43984398

43994399
SET_VARSIZE(poly, size);
@@ -4468,7 +4468,7 @@ box_poly(PG_FUNCTION_ARGS)
44684468
int size;
44694469

44704470
/* map four corners of the box to a polygon */
4471-
size = offsetof(POLYGON, p[0]) +sizeof(poly->p[0]) * 4;
4471+
size = offsetof(POLYGON, p) +sizeof(poly->p[0]) * 4;
44724472
poly = (POLYGON *) palloc(size);
44734473

44744474
SET_VARSIZE(poly, size);
@@ -4502,7 +4502,7 @@ poly_path(PG_FUNCTION_ARGS)
45024502
* Never overflows: the old size fit in MaxAllocSize, and the new size is
45034503
* smaller by a small constant.
45044504
*/
4505-
size = offsetof(PATH, p[0]) +sizeof(path->p[0]) * poly->npts;
4505+
size = offsetof(PATH, p) +sizeof(path->p[0]) * poly->npts;
45064506
path = (PATH *) palloc(size);
45074507

45084508
SET_VARSIZE(path, size);
@@ -5181,7 +5181,7 @@ circle_poly(PG_FUNCTION_ARGS)
51815181
errmsg("must request at least 2 points")));
51825182

51835183
base_size = sizeof(poly->p[0]) * npts;
5184-
size = offsetof(POLYGON, p[0]) +base_size;
5184+
size = offsetof(POLYGON, p) +base_size;
51855185

51865186
/* Check for integer overflow */
51875187
if (base_size / npts != sizeof(poly->p[0]) || size <= base_size)

‎src/backend/utils/cache/catcache.c

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1590,7 +1590,7 @@ SearchCatCacheList(CatCache *cache,
15901590
oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
15911591
nmembers = list_length(ctlist);
15921592
cl = (CatCList *)
1593-
palloc(sizeof(CatCList) + nmembers * sizeof(CatCTup *));
1593+
palloc(offsetof(CatCList, members) +nmembers * sizeof(CatCTup *));
15941594
heap_copytuple_with_tuple(ntp, &cl->tuple);
15951595
MemoryContextSwitchTo(oldcxt);
15961596
heap_freetuple(ntp);

‎src/bin/pg_dump/dumputils.c

Lines changed: 1 addition & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -1216,9 +1216,8 @@ simple_string_list_append(SimpleStringList *list, const char *val)
12161216
{
12171217
SimpleStringListCell *cell;
12181218

1219-
/* this calculation correctly accounts for the null trailing byte */
12201219
cell = (SimpleStringListCell *)
1221-
pg_malloc(sizeof(SimpleStringListCell) + strlen(val));
1220+
pg_malloc(offsetof(SimpleStringListCell, val) +strlen(val) + 1);
12221221

12231222
cell->next = NULL;
12241223
strcpy(cell->val, val);

‎src/bin/pg_dump/dumputils.h

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -38,7 +38,7 @@ typedef struct SimpleOidList
3838
typedef struct SimpleStringListCell
3939
{
4040
struct SimpleStringListCell *next;
41-
char val[1]; /* VARIABLE LENGTH FIELD */
41+
char val[FLEXIBLE_ARRAY_MEMBER]; /* null-terminated string here */
4242
} SimpleStringListCell;
4343

4444
typedef struct SimpleStringList

‎src/include/access/gin_private.h

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -322,7 +322,7 @@ typedef struct GinOptions
322322
{
323323
int32 vl_len_; /* varlena header (do not touch directly!) */
324324
bool useFastUpdate; /* use fast updates? */
325-
int pendingListCleanupSize; /* maximum size of pending list */
325+
int pendingListCleanupSize; /* maximum size of pending list */
326326
} GinOptions;
327327

328328
#define GIN_DEFAULT_USE_FASTUPDATE true
@@ -389,7 +389,7 @@ typedef struct
389389
{
390390
ItemPointerData first; /* first item in this posting list (unpacked) */
391391
uint16 nbytes; /* number of bytes that follow */
392-
unsigned char bytes[1]; /* varbyte encoded items (variable length) */
392+
unsigned char bytes[FLEXIBLE_ARRAY_MEMBER]; /* varbyte encoded items */
393393
} GinPostingList;
394394

395395
#define SizeOfGinPostingList(plist) (offsetof(GinPostingList, bytes) + SHORTALIGN((plist)->nbytes) )

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