diff options
| -rw-r--r-- | src/backend/access/common/toast_internals.c | 4 | ||||
| -rw-r--r-- | src/backend/commands/async.c | 14 | ||||
| -rw-r--r-- | src/backend/storage/large_object/inv_api.c | 8 | ||||
| -rw-r--r-- | src/include/c.h | 10 |
4 files changed, 11 insertions, 25 deletions
diff --git a/src/backend/access/common/toast_internals.c b/src/backend/access/common/toast_internals.c index 81dbd67c725..63b848473f8 100644 --- a/src/backend/access/common/toast_internals.c +++ b/src/backend/access/common/toast_internals.c @@ -287,11 +287,9 @@ toast_save_datum(Relation rel, Datum value, bool t_isnull[3] = {0}; union { - struct varlena hdr; + alignas(int32) struct varlena hdr; /* this is to make the union big enough for a chunk: */ char data[TOAST_MAX_CHUNK_SIZE + VARHDRSZ]; - /* ensure union is aligned well enough: */ - int32 align_it; } chunk_data; int32 chunk_size; diff --git a/src/backend/commands/async.c b/src/backend/commands/async.c index e1cf659485a..eb86402cae4 100644 --- a/src/backend/commands/async.c +++ b/src/backend/commands/async.c @@ -1987,14 +1987,10 @@ asyncQueueProcessPageEntries(QueuePosition *current, /* * We copy the entries into a local buffer to avoid holding the SLRU lock * while we transmit them to our frontend. The local buffer must be - * adequately aligned, so use a union. + * adequately aligned. */ - union - { - char buf[QUEUE_PAGESIZE]; - AsyncQueueEntry align; - } local_buf; - char *local_buf_end = local_buf.buf; + alignas(AsyncQueueEntry) char local_buf[QUEUE_PAGESIZE]; + char *local_buf_end = local_buf; slotno = SimpleLruReadPage_ReadOnly(NotifyCtl, curpage, InvalidTransactionId); @@ -2082,8 +2078,8 @@ asyncQueueProcessPageEntries(QueuePosition *current, * Now that we have let go of the SLRU bank lock, send the notifications * to our backend */ - Assert(local_buf_end - local_buf.buf <= BLCKSZ); - for (char *p = local_buf.buf; p < local_buf_end;) + Assert(local_buf_end - local_buf <= BLCKSZ); + for (char *p = local_buf; p < local_buf_end;) { AsyncQueueEntry *qe = (AsyncQueueEntry *) p; diff --git a/src/backend/storage/large_object/inv_api.c b/src/backend/storage/large_object/inv_api.c index f6d2f9dba13..2bd872d6581 100644 --- a/src/backend/storage/large_object/inv_api.c +++ b/src/backend/storage/large_object/inv_api.c @@ -556,11 +556,9 @@ inv_write(LargeObjectDesc *obj_desc, const char *buf, int nbytes) bool pfreeit; union { - bytea hdr; + alignas(int32) bytea hdr; /* this is to make the union big enough for a LO data chunk: */ char data[LOBLKSIZE + VARHDRSZ]; - /* ensure union is aligned well enough: */ - int32 align_it; } workbuf = {0}; char *workb = VARDATA(&workbuf.hdr); HeapTuple newtup; @@ -747,11 +745,9 @@ inv_truncate(LargeObjectDesc *obj_desc, int64 len) Form_pg_largeobject olddata; union { - bytea hdr; + alignas(int32) bytea hdr; /* this is to make the union big enough for a LO data chunk: */ char data[LOBLKSIZE + VARHDRSZ]; - /* ensure union is aligned well enough: */ - int32 align_it; } workbuf = {0}; char *workb = VARDATA(&workbuf.hdr); HeapTuple newtup; diff --git a/src/include/c.h b/src/include/c.h index 8e887bec0b2..729eb8a27de 100644 --- a/src/include/c.h +++ b/src/include/c.h @@ -1117,15 +1117,11 @@ pg_noreturn extern void ExceptionalCondition(const char *conditionName, * Use this, not "char buf[BLCKSZ]", to declare a field or local variable * holding a page buffer, if that page might be accessed as a page. Otherwise * the variable might be under-aligned, causing problems on alignment-picky - * hardware. We include both "double" and "int64" in the union to ensure that - * the compiler knows the value must be MAXALIGN'ed (cf. configure's - * computation of MAXIMUM_ALIGNOF). + * hardware. */ -typedef union PGAlignedBlock +typedef struct PGAlignedBlock { - char data[BLCKSZ]; - double force_align_d; - int64 force_align_i64; + alignas(MAXIMUM_ALIGNOF) char data[BLCKSZ]; } PGAlignedBlock; /* |