Make use of the flexible-array feature of C99, when available, to try to

pacify -fsanitize=strict-bounds.  This check-in fixes the core. There is
more yet to do in FTS3, RTREE, and in FTS5.

FossilOrigin-Name: 6fd6b32d06bd6a705e5140cd613af823b8183a6f6a9ceeeedfcf5e8b50821d68

17 files changed, 175 insertions, 108 deletions

diff --git a/manifest b/manifest
index eb3d849e1..549a0c86d 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\san\sinternal\sdoc\stypo\sreported\sin\s[forum:e25e581f917|forum\spost\se25e581f917].
-D 2025-03-14T12:37:36.487
+C Make\suse\sof\sthe\sflexible-array\sfeature\sof\sC99,\swhen\savailable,\sto\stry\sto\npacify\s-fsanitize=strict-bounds.\s\sThis\scheck-in\sfixes\sthe\score.\sThere\sis\nmore\syet\sto\sdo\sin\sFTS3,\sRTREE,\sand\sin\sFTS5.
+D 2025-03-14T18:10:02.673
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md e108e1e69ae8e8a59e93c455654b8ac9356a11720d3345df2a4743e9590fb20d
@@ -725,14 +725,14 @@ F src/btmutex.c 30dada73a819a1ef5b7583786370dce1842e12e1ad941e4d05ac29695528daea
 F src/btree.c 00fcee37947641f48d4b529d96143e74d056b7afa8f26d61292c90ee59c056b2
 F src/btree.h 18e5e7b2124c23426a283523e5f31a4bff029131b795bb82391f9d2f3136fc50
 F src/btreeInt.h 9c0f9ea5c9b5f4dcaea18111d43efe95f2ac276cd86d770dce10fd99ccc93886
-F src/build.c 20793695ef64d2d0c147501e37f344f828f09f16d346a987b516316186030996
+F src/build.c 3fe9b9d0f411cc2139a2d5ffa1c9b555417f89332f4dbf7f8e311c2e69e40c81
 F src/callback.c acae8c8dddda41ee85cfdf19b926eefe830f371069f8aadca3aa39adf5b1c859
 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
 F src/date.c 9db4d604e699a73e10b8e85a44db074a1f04c0591a77e2abfd77703f50dce1e9
 F src/dbpage.c 2e677acb658a29965e55398bbc61161cb7819da538057c8032adac7ab8e4a8c0
 F src/dbstat.c 73362c0df0f40ad5523a6f5501224959d0976757b511299bf892313e79d14f5c
 F src/delete.c 03a77ba20e54f0f42ebd8eddf15411ed6bdb06a2c472ac4b6b336521bf7cea42
-F src/expr.c f27e2692e65f0600cf4c989ec2af36bdfab52ada6365c0cc0f434630157b877f
+F src/expr.c 61c3baab38f1b50eb4696e1f37c8f7ae1d1ecbfc1a35d446cfd1886624784131
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c 928ed2517e8732113d2b9821aa37af639688d752f4ea9ac6e0e393d713eeb76f
 F src/func.c 7686ea382b20e8bfe2ab9de76150c99ee7b6e83523561f3c7787e0f68cb435c2
@@ -745,7 +745,7 @@ F src/insert.c a5f0366266be993ebf533808f22cb7a788624805b55bc45424ceed3f48c54a16
 F src/json.c 81e2012796a0e139b18c50ee3444c8ef86a020ab360511882216f5b610657e0c
 F src/legacy.c d7874bc885906868cd51e6c2156698f2754f02d9eee1bae2d687323c3ca8e5aa
 F src/loadext.c 7432c944ff197046d67a1207790a1b13eec4548c85a9457eb0896bb3641dfb36
-F src/main.c 5102588cbe7668d5ee19fd9945546e4f1fd99e41815432decf5dd29f01f55597
+F src/main.c 07f78d917ffcdf327982840cfd8e855fd000527a2ea5ace372ce4febcbd0bf97
 F src/malloc.c 410e570b30c26cc36e3372577df50f7a96ee3eed5b2b161c6b6b48773c650c5e
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c 3bb59158c38e05f6270e761a9f435bf19827a264c13d1631c58b84bdc96d73b2
@@ -779,14 +779,14 @@ F src/pragma.c 30b535d0a66348df844ee36f890617b4cf45e9a22dcbc47ec3ca92909c50aaf1
 F src/prepare.c 1832be043fce7d489959aae6f994c452d023914714c4d5457beaed51c0f3d126
 F src/printf.c 33fc0d7643c848a098afdcb6e1db6de12379d47084b1cd0912cfce1d09345e44
 F src/random.c 606b00941a1d7dd09c381d3279a058d771f406c5213c9932bbd93d5587be4b9c
-F src/resolve.c 626c24b258b111f75c22107aa5614ad89810df3026f5ca071116d3fe75925c75
+F src/resolve.c 20e1fbe8f840ffc0cd835e33f68a802a22e34faa918d7a269f3de242fda02f99
 F src/rowset.c 8432130e6c344b3401a8874c3cb49fefe6873fec593294de077afea2dce5ec97
-F src/select.c df63f64ef91c132dd12d37c876653f8b5493d2d5cf330a27158912ee5a065451
+F src/select.c 8c273248e38a8a7286abe3f41c1931cc65eff602fef128acc0cc0484e1b7abb3
 F src/shell.c.in 248050551cad788f8bb4b4728e00d8e36a10130d2d101e55cd51cfee03df91ff
 F src/sqlite.h.in fd70afd92948cf7cc93f687ac960bad1b0b6fbc436752419eff2fd65a1809380
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 3f046c04ea3595d6bfda99b781926b17e672fd6d27da2ba6d8d8fc39981dcb54
-F src/sqliteInt.h 130217107c0425ab43d098c6eadf8aa2e1a037e26d79384127e2d950b27eec77
+F src/sqliteInt.h 79d0f2705e62a1acaa11c10ac723749726ebbd96fb9be9f93c31fb44bdd4da1f
 F src/sqliteLimit.h 6d817c28a8f19af95e6f4921933b7fbbca48a962bce0eb0ec81e8bb3ef38e68b
 F src/status.c 0e72e4f6be6ccfde2488eb63210297e75f569f3ce9920f6c3d77590ec6ce5ffd
 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
@@ -844,30 +844,30 @@ F src/test_wsd.c 41cadfd9d97fe8e3e4e44f61a4a8ccd6f7ca8fe9
 F src/threads.c 4ae07fa022a3dc7c5beb373cf744a85d3c5c6c3c
 F src/tokenize.c 3e37ac2b6cbb9b0abe33827b0153c27595269afd7152b48019808974481aca2c
 F src/treeview.c d85ce76e6d1498d781957c07cb234da6d77ce0ed2d196480d516f54dabc62279
-F src/trigger.c da3c25786870d8bf97cd46b493374c2375d1abaf20a9b0f5f8629a3f2f2ce383
+F src/trigger.c 3ffb8ed6b64dbcc0ccae6e82435d01be3bf547e13b814e2d46f7df9bef84748e
 F src/update.c 3e5e7ff66fa19ebe4d1b113d480639a24cc1175adbefabbd1a948a07f28e37cf
 F src/upsert.c 215328c3f91623c520ec8672c44323553f12caeb4f01b1090ebdca99fdf7b4f1
 F src/utf.c d4d55ca95106a2029ec1cdbd2497a34e69ea1d338f1a9d80ef15ebf4ff01690d
 F src/util.c 36fb1150062957280777655976f3f9a75db236cb8207a0770ceae8d5ec17fcd3
 F src/vacuum.c fbfc3e074c865d2b5b10b8a65a3783275b80c152653590690747a102bb6cc770
-F src/vdbe.c 014769c8f7e528d59f5a8e25d0035258396cc2c755673dee29885b6049725ee6
+F src/vdbe.c b5deed01000b3970cfca089dc531cf9342afd96d00cc8b4ad26d303f088116ee
 F src/vdbe.h 31eddcffc1d14c76c2a20fe4e137e1ee43d44f370896fae14a067052801a3625
-F src/vdbeInt.h 078b1c15b26587b54c1c1879d0d2f4dec812b9de4c337fed9faf73fbcc3bf091
+F src/vdbeInt.h 11041d559992165651413e5868a907f698a2ec7af169fb2d20eb058a9ccd2313
 F src/vdbeapi.c cb8eb9e41a16f5fa3ce5b8f3910edfbba336d10156cfb7a79f92cf7bf443977b
-F src/vdbeaux.c d7ef1a0a7233589d789eda1ba9ffa4b0ea61fca9651e4f47fb4250d03d62bcaf
+F src/vdbeaux.c 932105750c15378176980288daea80008ffdac360716ae4e7c7f85bf462d272d
 F src/vdbeblob.c b1b4032cac46b41e44b957c4d00aee9851f862dfd85ecb68116ba49884b03dfd
 F src/vdbemem.c 571ae3116dbf840a62c4aaa6bc09d577dfef8ad4d3978cf37275bb5f9653217b
-F src/vdbesort.c f7ce6eb4c0e8b0273329d2f43b8b6e5ebe8f2d853fc323d5787dada702ea0b66
+F src/vdbesort.c 49e366d0216c782eba287bf602384e4330d2526a22f1275492d2785ce103c79b
 F src/vdbetrace.c fe0bc29ebd4e02c8bc5c1945f1d2e6be5927ec12c06d89b03ef2a4def34bf823
 F src/vdbevtab.c fc46b9cbd759dc013f0b3724549cc0d71379183c667df3a5988f7e2f1bd485f3
 F src/vtab.c 828221bdbeaaa6d62126ee6d07fd4ec0d09dcaea846f87ad01944d8b7e548859
 F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
-F src/wal.c 2c69a5f92270429db72d853691b0640c76c671d5b2465396dadb9d9873e1efce
+F src/wal.c 554a6b1afaaecb98cb47bb598bccf1374c9d3b624e5c4c3c4eb2ad364cc579f8
 F src/wal.h ba252daaa94f889f4b2c17c027e823d9be47ce39da1d3799886bbd51f0490452
 F src/walker.c d5006d6b005e4ea7302ad390957a8d41ed83faa177e412f89bc5600a7462a014
-F src/where.c 12cca5dfbe96e2589f951c43c0720fc58e52611787c37d85a0d9c10376202e8b
-F src/whereInt.h d20cddddb1d61b18d5cb1fcfa9b77fbeebbc4afe44d996e603452a23b3009ee1
-F src/wherecode.c 5baa06f0daae7d38aca1d4814030b82ad4f127fe6bad18f0644776a474f6088b
+F src/where.c e80177e452b4e436abc6ece0cb0249631000434f2a7425cc1df709015fce74ad
+F src/whereInt.h 8373791e8dfbef3ca0d4ad7eab350be860b2740c44d94d0c54d2a8d36209c41a
+F src/wherecode.c 0d3de258d7922aede028841c6e0060633c50be26737c92cc62ce8be280535430
 F src/whereexpr.c 2415c8eee5ff89a8b709d7d83d71c1ff986cd720d0520057e1d8a5371339012a
 F src/window.c d01227141f622f24fbe36ca105fbe6ef023f9fd98f1ccd65da95f88886565db5
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
@@ -2213,8 +2213,11 @@ F tool/version-info.c 3b36468a90faf1bbd59c65fd0eb66522d9f941eedd364fabccd7227350
 F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee87c1b31a7
 F tool/warnings.sh 49a486c5069de041aedcbde4de178293e0463ae9918ecad7539eedf0ec77a139
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P f786de8d1873cd27b1bf83273a1e100e9d481144674888ccf65974e003a3caad
-R d7baa5b59cd39b651d61c163fdc55c15
-U stephan
-Z bd2d36d9f3639b6b3b36c30d817df77d
+P fa6f6ccdffc50024624306900efd2538c7415d8bdd0f02835b2e9c05adab3cf1
+R a7f539cde629f0570849a89a860ffc9d
+T *branch * flex-array
+T *sym-flex-array *
+T -sym-trunk *
+U drh
+Z ea27c767023e4b4e578a073476796f47
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 38ff83c8d..45864ab06 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-fa6f6ccdffc50024624306900efd2538c7415d8bdd0f02835b2e9c05adab3cf1
+6fd6b32d06bd6a705e5140cd613af823b8183a6f6a9ceeeedfcf5e8b50821d68
diff --git a/src/build.c b/src/build.c
index 907494b19..267962666 100644
--- a/src/build.c
+++ b/src/build.c
@@ -3633,7 +3633,7 @@ void sqlite3CreateForeignKey(
   }else{
     nCol = pFromCol->nExpr;
   }
-  nByte = sizeof(*pFKey) + (nCol-1)*sizeof(pFKey->aCol[0]) + pTo->n + 1;
+  nByte = SZ_FKEY(nCol) + pTo->n + 1;
   if( pToCol ){
     for(i=0; i<pToCol->nExpr; i++){
       nByte += sqlite3Strlen30(pToCol->a[i].zEName) + 1;
@@ -4692,12 +4692,11 @@ IdList *sqlite3IdListAppend(Parse *pParse, IdList *pList, Token *pToken){
   sqlite3 *db = pParse->db;
   int i;
   if( pList==0 ){
-    pList = sqlite3DbMallocZero(db, sizeof(IdList) );
+    pList = sqlite3DbMallocZero(db, SZ_IDLIST(1));
     if( pList==0 ) return 0;
   }else{
     IdList *pNew;
-    pNew = sqlite3DbRealloc(db, pList,
-                 sizeof(IdList) + pList->nId*sizeof(pList->a));
+    pNew = sqlite3DbRealloc(db, pList, SZ_IDLIST(pList->nId+1));
     if( pNew==0 ){
       sqlite3IdListDelete(db, pList);
       return 0;
@@ -4796,8 +4795,7 @@ SrcList *sqlite3SrcListEnlarge(
       return 0;
     }
     if( nAlloc>SQLITE_MAX_SRCLIST ) nAlloc = SQLITE_MAX_SRCLIST;
-    pNew = sqlite3DbRealloc(db, pSrc,
-               sizeof(*pSrc) + (nAlloc-1)*sizeof(pSrc->a[0]) );
+    pNew = sqlite3DbRealloc(db, pSrc, SZ_SRCLIST(nAlloc));
     if( pNew==0 ){
       assert( db->mallocFailed );
       return 0;
@@ -4872,7 +4870,7 @@ SrcList *sqlite3SrcListAppend(
   assert( pParse->db!=0 );
   db = pParse->db;
   if( pList==0 ){
-    pList = sqlite3DbMallocRawNN(pParse->db, sizeof(SrcList) );
+    pList = sqlite3DbMallocRawNN(pParse->db, SZ_SRCLIST(1));
     if( pList==0 ) return 0;
     pList->nAlloc = 1;
     pList->nSrc = 1;
@@ -5758,10 +5756,9 @@ With *sqlite3WithAdd(
   }
 
   if( pWith ){
-    sqlite3_int64 nByte = sizeof(*pWith) + (sizeof(pWith->a[1]) * pWith->nCte);
-    pNew = sqlite3DbRealloc(db, pWith, nByte);
+    pNew = sqlite3DbRealloc(db, pWith, SZ_WITH(pWith->nCte+1));
   }else{
-    pNew = sqlite3DbMallocZero(db, sizeof(*pWith));
+    pNew = sqlite3DbMallocZero(db, SZ_WITH(1));
   }
   assert( (pNew!=0 && zName!=0) || db->mallocFailed );
 
diff --git a/src/expr.c b/src/expr.c
index a3c41a1f5..dd5ea2038 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -1738,7 +1738,7 @@ static Expr *exprDup(
 With *sqlite3WithDup(sqlite3 *db, With *p){
   With *pRet = 0;
   if( p ){
-    sqlite3_int64 nByte = sizeof(*p) + sizeof(p->a[0]) * (p->nCte-1);
+    sqlite3_int64 nByte = SZ_WITH(p->nCte);
     pRet = sqlite3DbMallocZero(db, nByte);
     if( pRet ){
       int i;
@@ -1865,11 +1865,9 @@ ExprList *sqlite3ExprListDup(sqlite3 *db, const ExprList *p, int flags){
 SrcList *sqlite3SrcListDup(sqlite3 *db, const SrcList *p, int flags){
   SrcList *pNew;
   int i;
-  int nByte;
   assert( db!=0 );
   if( p==0 ) return 0;
-  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
-  pNew = sqlite3DbMallocRawNN(db, nByte );
+  pNew = sqlite3DbMallocRawNN(db, SZ_SRCLIST(p->nSrc) );
   if( pNew==0 ) return 0;
   pNew->nSrc = pNew->nAlloc = p->nSrc;
   for(i=0; i<p->nSrc; i++){
@@ -1931,7 +1929,7 @@ IdList *sqlite3IdListDup(sqlite3 *db, const IdList *p){
   int i;
   assert( db!=0 );
   if( p==0 ) return 0;
-  pNew = sqlite3DbMallocRawNN(db, sizeof(*pNew)+(p->nId-1)*sizeof(p->a[0]) );
+  pNew = sqlite3DbMallocRawNN(db, SZ_IDLIST(p->nId));
   if( pNew==0 ) return 0;
   pNew->nId = p->nId;
   for(i=0; i<p->nId; i++){
@@ -2015,7 +2013,7 @@ SQLITE_NOINLINE ExprList *sqlite3ExprListAppendNew(
   struct ExprList_item *pItem;
   ExprList *pList;
 
-  pList = sqlite3DbMallocRawNN(db, sizeof(ExprList)+sizeof(pList->a[0])*4 );
+  pList = sqlite3DbMallocRawNN(db, SZ_EXPRLIST(4));
   if( pList==0 ){
     sqlite3ExprDelete(db, pExpr);
     return 0;
@@ -2035,8 +2033,7 @@ SQLITE_NOINLINE ExprList *sqlite3ExprListAppendGrow(
   struct ExprList_item *pItem;
   ExprList *pNew;
   pList->nAlloc *= 2;
-  pNew = sqlite3DbRealloc(db, pList,
-       sizeof(*pList)+(pList->nAlloc-1)*sizeof(pList->a[0]));
+  pNew = sqlite3DbRealloc(db, pList, SZ_EXPRLIST(pList->nAlloc));
   if( pNew==0 ){
     sqlite3ExprListDelete(db, pList);
     sqlite3ExprDelete(db, pExpr);
diff --git a/src/main.c b/src/main.c
index ba2faf0b7..9b67de815 100644
--- a/src/main.c
+++ b/src/main.c
@@ -3845,7 +3845,7 @@ int sqlite3_set_clientdata(
     return SQLITE_OK;
   }else{
     size_t n = strlen(zName);
-    p = sqlite3_malloc64( sizeof(DbClientData)+n+1 );
+    p = sqlite3_malloc64( SZ_DBCLIENTDATA(n+1) );
     if( p==0 ){
       if( xDestructor ) xDestructor(pData);
       sqlite3_mutex_leave(db->mutex);
diff --git a/src/resolve.c b/src/resolve.c
index 54ce4fb1e..c3ab2d557 100644
--- a/src/resolve.c
+++ b/src/resolve.c
@@ -2277,20 +2277,22 @@ int sqlite3ResolveSelfReference(
   Expr *pExpr,     /* Expression to resolve.  May be NULL. */
   ExprList *pList  /* Expression list to resolve.  May be NULL. */
 ){
-  SrcList sSrc;                   /* Fake SrcList for pParse->pNewTable */
+  SrcList *pSrc;                  /* Fake SrcList for pParse->pNewTable */
   NameContext sNC;                /* Name context for pParse->pNewTable */
   int rc;
+  u8 srcSpace[SZ_SRCLIST_1];     /* Memory space for the fake SrcList */
 
   assert( type==0 || pTab!=0 );
   assert( type==NC_IsCheck || type==NC_PartIdx || type==NC_IdxExpr
           || type==NC_GenCol || pTab==0 );
   memset(&sNC, 0, sizeof(sNC));
-  memset(&sSrc, 0, sizeof(sSrc));
+  pSrc = (SrcList*)srcSpace;
+  memset(pSrc, 0, SZ_SRCLIST_1);
   if( pTab ){
-    sSrc.nSrc = 1;
-    sSrc.a[0].zName = pTab->zName;
-    sSrc.a[0].pSTab = pTab;
-    sSrc.a[0].iCursor = -1;
+    pSrc->nSrc = 1;
+    pSrc->a[0].zName = pTab->zName;
+    pSrc->a[0].pSTab = pTab;
+    pSrc->a[0].iCursor = -1;
     if( pTab->pSchema!=pParse->db->aDb[1].pSchema ){
       /* Cause EP_FromDDL to be set on TK_FUNCTION nodes of non-TEMP
       ** schema elements */
@@ -2298,7 +2300,7 @@ int sqlite3ResolveSelfReference(
     }
   }
   sNC.pParse = pParse;
-  sNC.pSrcList = &sSrc;
+  sNC.pSrcList = pSrc;
   sNC.ncFlags = type | NC_IsDDL;
   if( (rc = sqlite3ResolveExprNames(&sNC, pExpr))!=SQLITE_OK ) return rc;
   if( pList ) rc = sqlite3ResolveExprListNames(&sNC, pList);
diff --git a/src/select.c b/src/select.c
index 904290223..eedbd8281 100644
--- a/src/select.c
+++ b/src/select.c
@@ -154,7 +154,7 @@ Select *sqlite3SelectNew(
   pNew->addrOpenEphm[0] = -1;
   pNew->addrOpenEphm[1] = -1;
   pNew->nSelectRow = 0;
-  if( pSrc==0 ) pSrc = sqlite3DbMallocZero(pParse->db, sizeof(*pSrc));
+  if( pSrc==0 ) pSrc = sqlite3DbMallocZero(pParse->db, SZ_SRCLIST_1);
   pNew->pSrc = pSrc;
   pNew->pWhere = pWhere;
   pNew->pGroupBy = pGroupBy;
@@ -1537,8 +1537,8 @@ static void selectInnerLoop(
 ** X extra columns.
 */
 KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N, int X){
-  int nExtra = (N+X)*(sizeof(CollSeq*)+1) - sizeof(CollSeq*);
-  KeyInfo *p = sqlite3DbMallocRawNN(db, sizeof(KeyInfo) + nExtra);
+  int nExtra = (N+X)*(sizeof(CollSeq*)+1);
+  KeyInfo *p = sqlite3DbMallocRawNN(db, SZ_KEYINFO(0) + nExtra);
   if( p ){
     p->aSortFlags = (u8*)&p->aColl[N+X];
     p->nKeyField = (u16)N;
@@ -1546,7 +1546,7 @@ KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N, int X){
     p->enc = ENC(db);
     p->db = db;
     p->nRef = 1;
-    memset(&p[1], 0, nExtra);
+    memset(p->aColl, 0, nExtra);
   }else{
     return (KeyInfo*)sqlite3OomFault(db);
   }
@@ -6062,7 +6062,7 @@ static int selectExpander(Walker *pWalker, Select *p){
   pEList = p->pEList;
   if( pParse->pWith && (p->selFlags & SF_View) ){
     if( p->pWith==0 ){
-      p->pWith = (With*)sqlite3DbMallocZero(db, sizeof(With));
+      p->pWith = (With*)sqlite3DbMallocZero(db, SZ_WITH(1) );
       if( p->pWith==0 ){
         return WRC_Abort;
       }
@@ -7250,7 +7250,7 @@ static int countOfViewOptimization(Parse *pParse, Select *p){
   pExpr = 0;
   pSub = sqlite3SubqueryDetach(db, pFrom);
   sqlite3SrcListDelete(db, p->pSrc);
-  p->pSrc = sqlite3DbMallocZero(pParse->db, sizeof(*p->pSrc));
+  p->pSrc = sqlite3DbMallocZero(pParse->db, SZ_SRCLIST_1);
   while( pSub ){
     Expr *pTerm;
     pPrior = pSub->pPrior;
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 034f98690..7b71ace56 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -769,6 +769,16 @@
 #endif
 
 /*
+** Work around C99 "flex-array" syntax for pre-C99 compilers, so as
+** to avoid complaints from -fsanitize=strict-bounds.
+*/
+#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
+# define FLEXARRAY
+#else
+# define FLEXARRAY 1
+#endif
+
+/*
 ** Macros to compute minimum and maximum of two numbers.
 */
 #ifndef MIN
@@ -2577,9 +2587,13 @@ struct FKey {
   struct sColMap {      /* Mapping of columns in pFrom to columns in zTo */
     int iFrom;            /* Index of column in pFrom */
     char *zCol;           /* Name of column in zTo.  If NULL use PRIMARY KEY */
-  } aCol[1];            /* One entry for each of nCol columns */
+  } aCol[FLEXARRAY];      /* One entry for each of nCol columns */
 };
 
+/* The size (in bytes) of an FKey object holding N columns.  The answer
+** does NOT include space to hold the zTo name. */
+#define SZ_FKEY(N)  (offsetof(FKey,aCol)+(N)*sizeof(struct sColMap))
+
 /*
 ** SQLite supports many different ways to resolve a constraint
 ** error.  ROLLBACK processing means that a constraint violation
@@ -2641,9 +2655,12 @@ struct KeyInfo {
   u16 nAllField;      /* Total columns, including key plus others */
   sqlite3 *db;        /* The database connection */
   u8 *aSortFlags;     /* Sort order for each column. */
-  CollSeq *aColl[1];  /* Collating sequence for each term of the key */
+  CollSeq *aColl[FLEXARRAY]; /* Collating sequence for each term of the key */
 };
 
+/* The size (in bytes) of a KeyInfo object with up to N fields */
+#define SZ_KEYINFO(N)  (offsetof(KeyInfo,aColl) + (N)*sizeof(CollSeq*))
+
 /*
 ** Allowed bit values for entries in the KeyInfo.aSortFlags[] array.
 */
@@ -3216,9 +3233,14 @@ struct ExprList {
       int iConstExprReg;   /* Register in which Expr value is cached. Used only
                            ** by Parse.pConstExpr */
     } u;
-  } a[1];                  /* One slot for each expression in the list */
+  } a[FLEXARRAY];          /* One slot for each expression in the list */
 };
 
+/* The size (in bytes) of an ExprList object that is big enough to hold
+** as many as N expressions. */
+#define SZ_EXPRLIST(N)  \
+             (offsetof(ExprList,a) + (N)*sizeof(struct ExprList_item))
+
 /*
 ** Allowed values for Expr.a.eEName
 */
@@ -3246,9 +3268,12 @@ struct IdList {
   int nId;         /* Number of identifiers on the list */
   struct IdList_item {
     char *zName;      /* Name of the identifier */
-  } a[1];
+  } a[FLEXARRAY];
 };
 
+/* The size (in bytes) of an IdList object that can hold up to N IDs. */
+#define SZ_IDLIST(N)  (offsetof(IdList,a)+(N)*sizeof(struct IdList_item))
+
 /*
 ** Allowed values for IdList.eType, which determines which value of the a.u4
 ** is valid.
@@ -3368,11 +3393,19 @@ struct OnOrUsing {
 **
 */
 struct SrcList {
-  int nSrc;        /* Number of tables or subqueries in the FROM clause */
-  u32 nAlloc;      /* Number of entries allocated in a[] below */
-  SrcItem a[1];    /* One entry for each identifier on the list */
+  int nSrc;             /* Number of tables or subqueries in the FROM clause */
+  u32 nAlloc;           /* Number of entries allocated in a[] below */
+  SrcItem a[FLEXARRAY]; /* One entry for each identifier on the list */
 };
 
+/* Size (in bytes) of a SrcList object that can hold as many as N
+** SrcItem objects. */
+#define SZ_SRCLIST(N) (offsetof(SrcList,a)+(N)*sizeof(SrcItem))
+
+/* Size (in bytes( of a SrcList object that holds 1 SrcItem.  This is a
+** special case of SZ_SRCITEM(1) that comes up often. */
+#define SZ_SRCLIST_1  (offsetof(SrcList,a)+sizeof(SrcItem))
+
 /*
 ** Permitted values of the SrcList.a.jointype field
 */
@@ -4436,9 +4469,13 @@ struct With {
   int nCte;               /* Number of CTEs in the WITH clause */
   int bView;              /* Belongs to the outermost Select of a view */
   With *pOuter;           /* Containing WITH clause, or NULL */
-  Cte a[1];               /* For each CTE in the WITH clause.... */
+  Cte a[FLEXARRAY];       /* For each CTE in the WITH clause.... */
 };
 
+/* The size (in bytes) of a With object that can hold as many
+** as N different CTEs. */
+#define SZ_WITH(N)  (offsetof(With,a) + (N)*sizeof(Cte))
+
 /*
 ** The Cte object is not guaranteed to persist for the entire duration
 ** of code generation.  (The query flattener or other parser tree
@@ -4467,9 +4504,13 @@ struct DbClientData {
   DbClientData *pNext;        /* Next in a linked list */
   void *pData;                /* The data */
   void (*xDestructor)(void*); /* Destructor.  Might be NULL */
-  char zName[1];              /* Name of this client data. MUST BE LAST */
+  char zName[FLEXARRAY];      /* Name of this client data. MUST BE LAST */
 };
 
+/* The size (in bytes) of a DbClientData object that can has a name
+** that is N bytes long, including the zero-terminator. */
+#define SZ_DBCLIENTDATA(N) (offsetof(DbClientData,zName)+(N))
+
 #ifdef SQLITE_DEBUG
 /*
 ** An instance of the TreeView object is used for printing the content of
diff --git a/src/trigger.c b/src/trigger.c
index 604c3ab42..779da5e5f 100644
--- a/src/trigger.c
+++ b/src/trigger.c
@@ -1039,7 +1039,8 @@ static void codeReturningTrigger(
   ExprList *pNew;
   Returning *pReturning;
   Select sSelect;
-  SrcList sFrom;
+  SrcList *pFrom;
+  u8 fromSpace[SZ_SRCLIST_1];
 
   assert( v!=0 );
   if( !pParse->bReturning ){
@@ -1055,13 +1056,14 @@ static void codeReturningTrigger(
     return;
   }
   memset(&sSelect, 0, sizeof(sSelect));
-  memset(&sFrom, 0, sizeof(sFrom));
+  pFrom = (SrcList*)fromSpace;
+  memset(pFrom, 0, SZ_SRCLIST_1);
   sSelect.pEList = sqlite3ExprListDup(db, pReturning->pReturnEL, 0);
-  sSelect.pSrc = &sFrom;
-  sFrom.nSrc = 1;
-  sFrom.a[0].pSTab = pTab;
-  sFrom.a[0].zName = pTab->zName; /* tag-20240424-1 */
-  sFrom.a[0].iCursor = -1;
+  sSelect.pSrc = pFrom;
+  pFrom->nSrc = 1;
+  pFrom->a[0].pSTab = pTab;
+  pFrom->a[0].zName = pTab->zName; /* tag-20240424-1 */
+  pFrom->a[0].iCursor = -1;
   sqlite3SelectPrep(pParse, &sSelect, 0);
   if( pParse->nErr==0 ){
     assert( db->mallocFailed==0 );
diff --git a/src/vdbe.c b/src/vdbe.c
index ed5687f25..6ded15c79 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -278,9 +278,9 @@ static VdbeCursor *allocateCursor(
 
   i64 nByte;
   VdbeCursor *pCx = 0;
-  nByte =
-      ROUND8P(sizeof(VdbeCursor)) + 2*sizeof(u32)*nField +
-      (eCurType==CURTYPE_BTREE?sqlite3BtreeCursorSize():0);
+  nByte = SZ_VDBECURSOR(nField);
+  assert( ROUND8(nByte)==nByte );
+  if( eCurType==CURTYPE_BTREE ) nByte += sqlite3BtreeCursorSize();
 
   assert( iCur>=0 && iCur<p->nCursor );
   if( p->apCsr[iCur] ){ /*OPTIMIZATION-IF-FALSE*/
@@ -313,8 +313,8 @@ static VdbeCursor *allocateCursor(
   pCx->nField = nField;
   pCx->aOffset = &pCx->aType[nField];
   if( eCurType==CURTYPE_BTREE ){
-    pCx->uc.pCursor = (BtCursor*)
-        &pMem->z[ROUND8P(sizeof(VdbeCursor))+2*sizeof(u32)*nField];
+    assert( ROUND8(SZ_VDBECURSOR(nField))==SZ_VDBECURSOR(nField) );
+    pCx->uc.pCursor = (BtCursor*)&pMem->z[SZ_VDBECURSOR(nField)];
     sqlite3BtreeCursorZero(pCx->uc.pCursor);
   }
   return pCx;
@@ -7705,7 +7705,7 @@ case OP_AggStep: {
   **
   ** Note: We could avoid this by using a regular memory cell from aMem[] for 
   ** the accumulator, instead of allocating one here. */
-  nAlloc = ROUND8P( sizeof(pCtx[0]) + (n-1)*sizeof(sqlite3_value*) );
+  nAlloc = ROUND8P( SZ_CONTEXT(n) );
   pCtx = sqlite3DbMallocRawNN(db, nAlloc + sizeof(Mem));
   if( pCtx==0 ) goto no_mem;
   pCtx->pOut = (Mem*)((u8*)pCtx + nAlloc);
diff --git a/src/vdbeInt.h b/src/vdbeInt.h
index 12af82726..a86453f56 100644
--- a/src/vdbeInt.h
+++ b/src/vdbeInt.h
@@ -133,12 +133,18 @@ struct VdbeCursor {
 #endif
   VdbeTxtBlbCache *pCache; /* Cache of large TEXT or BLOB values */
 
-  /* 2*nField extra array elements allocated for aType[], beyond the one
-  ** static element declared in the structure.  nField total array slots for
-  ** aType[] and nField+1 array slots for aOffset[] */
-  u32 aType[1];           /* Type values record decode.  MUST BE LAST */
+  /* Space is allocated for aType to hold at least 2*nField+1 entries:
+  ** nField slots for aType[] and nField+1 array slots for aOffset[] */
+  u32 aType[FLEXARRAY];    /* Type values record decode.  MUST BE LAST */
 };
 
+/*
+** The size (in bytes) of a VdbeCursor object that has an nField value of N
+** or less.  The value of SZ_VDBECURSOR(n) is guaranteed to be a multiple
+** of 8.
+*/
+#define SZ_VDBECURSOR(N) (offsetof(VdbeCursor,aType) + ((N)+1)*sizeof(u64))
+
 /* Return true if P is a null-only cursor
 */
 #define IsNullCursor(P) \
@@ -395,9 +401,16 @@ struct sqlite3_context {
   u8 enc;                 /* Encoding to use for results */
   u8 skipFlag;            /* Skip accumulator loading if true */
   u16 argc;               /* Number of arguments */
-  sqlite3_value *argv[1]; /* Argument set */
+  sqlite3_value *argv[FLEXARRAY]; /* Argument set */
 };
 
+/*
+** The size (in bytes) of an sqlite3_context object that holds N
+** argv[] arguments.
+*/
+#define SZ_CONTEXT(N)  \
+   (offsetof(sqlite3_context,argv)+(N)*sizeof(sqlite3_value*))
+
 
 /* The ScanStatus object holds a single value for the
 ** sqlite3_stmt_scanstatus() interface.
diff --git a/src/vdbeaux.c b/src/vdbeaux.c
index 6a8db6f39..ccb0f8867 100644
--- a/src/vdbeaux.c
+++ b/src/vdbeaux.c
@@ -445,12 +445,10 @@ int sqlite3VdbeAddFunctionCall(
   int eCallCtx          /* Calling context */
 ){
   Vdbe *v = pParse->pVdbe;
-  int nByte;
   int addr;
   sqlite3_context *pCtx;
   assert( v );
-  nByte = sizeof(*pCtx) + (nArg-1)*sizeof(sqlite3_value*);
-  pCtx = sqlite3DbMallocRawNN(pParse->db, nByte);
+  pCtx = sqlite3DbMallocRawNN(pParse->db, SZ_CONTEXT(nArg));
   if( pCtx==0 ){
     assert( pParse->db->mallocFailed );
     freeEphemeralFunction(pParse->db, (FuncDef*)pFunc);
diff --git a/src/vdbesort.c b/src/vdbesort.c
index c9da88f6e..9a7e0760c 100644
--- a/src/vdbesort.c
+++ b/src/vdbesort.c
@@ -332,9 +332,12 @@ struct VdbeSorter {
   u8 iPrev;                       /* Previous thread used to flush PMA */
   u8 nTask;                       /* Size of aTask[] array */
   u8 typeMask;
-  SortSubtask aTask[1];           /* One or more subtasks */
+  SortSubtask aTask[FLEXARRAY];   /* One or more subtasks */
 };
 
+/* Size (in bytes) of a VdbeSorter object that works with N or fewer subtasks */
+#define SZ_VDBESORTER(N)  (offsetof(VdbeSorter,aTask)+(N)*sizeof(SortSubtask))
+
 #define SORTER_TYPE_INTEGER 0x01
 #define SORTER_TYPE_TEXT    0x02
 
@@ -966,8 +969,8 @@ int sqlite3VdbeSorterInit(
   assert( pCsr->eCurType==CURTYPE_SORTER );
   assert( sizeof(KeyInfo) + UMXV(pCsr->pKeyInfo->nKeyField)*sizeof(CollSeq*)
                < 0x7fffffff );
-  szKeyInfo = sizeof(KeyInfo) + (pCsr->pKeyInfo->nKeyField-1)*sizeof(CollSeq*);
-  sz = sizeof(VdbeSorter) + nWorker * sizeof(SortSubtask);
+  szKeyInfo = SZ_KEYINFO(pCsr->pKeyInfo->nKeyField+1);
+  sz = SZ_VDBESORTER(nWorker+1);
 
   pSorter = (VdbeSorter*)sqlite3DbMallocZero(db, sz + szKeyInfo);
   pCsr->uc.pSorter = pSorter;
diff --git a/src/wal.c b/src/wal.c
index d374d6eb4..7f091a48c 100644
--- a/src/wal.c
+++ b/src/wal.c
@@ -597,9 +597,13 @@ struct WalIterator {
     u32 *aPgno;                   /* Array of page numbers. */
     int nEntry;                   /* Nr. of entries in aPgno[] and aIndex[] */
     int iZero;                    /* Frame number associated with aPgno[0] */
-  } aSegment[1];                  /* One for every 32KB page in the wal-index */
+  } aSegment[FLEXARRAY];          /* One for every 32KB page in the wal-index */
 };
 
+/* Size (in bytes) of a WalIterator object suitable for N or fewer segments */
+#define SZ_WALITERATOR(N)  \
+     (offsetof(WalIterator,aSegment)*(N)*sizeof(struct WalSegment))
+
 /*
 ** Define the parameters of the hash tables in the wal-index file. There
 ** is a hash-table following every HASHTABLE_NPAGE page numbers in the
@@ -1960,8 +1964,7 @@ static int walIteratorInit(Wal *pWal, u32 nBackfill, WalIterator **pp){
 
   /* Allocate space for the WalIterator object. */
   nSegment = walFramePage(iLast) + 1;
-  nByte = sizeof(WalIterator)
-        + (nSegment-1)*sizeof(struct WalSegment)
+  nByte = SZ_WALITERATOR(nSegment)
         + iLast*sizeof(ht_slot);
   p = (WalIterator *)sqlite3_malloc64(nByte
       + sizeof(ht_slot) * (iLast>HASHTABLE_NPAGE?HASHTABLE_NPAGE:iLast)
diff --git a/src/where.c b/src/where.c
index 127525006..ed6320349 100644
--- a/src/where.c
+++ b/src/where.c
@@ -35,11 +35,16 @@ struct HiddenIndexInfo {
   int eDistinct;           /* Value to return from sqlite3_vtab_distinct() */
   u32 mIn;                 /* Mask of terms that are <col> IN (...) */
   u32 mHandleIn;           /* Terms that vtab will handle as <col> IN (...) */
-  sqlite3_value *aRhs[1];  /* RHS values for constraints. MUST BE LAST
-                           ** because extra space is allocated to hold up
-                           ** to nTerm such values */
+  sqlite3_value *aRhs[FLEXARRAY];  /* RHS values for constraints. MUST BE LAST
+                                   ** Extra space is allocated to hold up
+                                   ** to nTerm such values */
 };
 
+/* Size (in bytes) of a HiddenIndeInfo object sufficient to hold as
+** many as N constraints */
+#define SZ_HIDDENINDEXINFO(N) \
+                  (offsetof(HiddenIndexInfo,aRhs) + (N)*sizeof(sqlite3_value*))
+
 /* Forward declaration of methods */
 static int whereLoopResize(sqlite3*, WhereLoop*, int);
 
@@ -1517,8 +1522,8 @@ static sqlite3_index_info *allocateIndexInfo(
   */
   pIdxInfo = sqlite3DbMallocZero(pParse->db, sizeof(*pIdxInfo)
                            + (sizeof(*pIdxCons) + sizeof(*pUsage))*nTerm
-                           + sizeof(*pIdxOrderBy)*nOrderBy + sizeof(*pHidden)
-                           + sizeof(sqlite3_value*)*nTerm );
+                           + sizeof(*pIdxOrderBy)*nOrderBy
+                           + SZ_HIDDENINDEXINFO(nTerm) );
   if( pIdxInfo==0 ){
     sqlite3ErrorMsg(pParse, "out of memory");
     return 0;
@@ -6712,10 +6717,7 @@ WhereInfo *sqlite3WhereBegin(
   ** field (type Bitmask) it must be aligned on an 8-byte boundary on
   ** some architectures. Hence the ROUND8() below.
   */
-  nByteWInfo = ROUND8P(sizeof(WhereInfo));
-  if( nTabList>1 ){
-    nByteWInfo = ROUND8P(nByteWInfo + (nTabList-1)*sizeof(WhereLevel));
-  }
+  nByteWInfo = SZ_WHEREINFO(nTabList);
   pWInfo = sqlite3DbMallocRawNN(db, nByteWInfo + sizeof(WhereLoop));
   if( db->mallocFailed ){
     sqlite3DbFree(db, pWInfo);
diff --git a/src/whereInt.h b/src/whereInt.h
index 8ba8a7072..1b0a02d8b 100644
--- a/src/whereInt.h
+++ b/src/whereInt.h
@@ -501,10 +501,15 @@ struct WhereInfo {
   Bitmask revMask;          /* Mask of ORDER BY terms that need reversing */
   WhereClause sWC;          /* Decomposition of the WHERE clause */
   WhereMaskSet sMaskSet;    /* Map cursor numbers to bitmasks */
-  WhereLevel a[1];          /* Information about each nest loop in WHERE */
+  WhereLevel a[FLEXARRAY];  /* Information about each nest loop in WHERE */
 };
 
 /*
+** The size (in bytes) of a WhereInfo object that holds N WhereLevels.
+*/
+#define SZ_WHEREINFO(N) (offsetof(WhereInfo,a)+(N)*sizeof(WhereLevel))
+
+/*
 ** Private interfaces - callable only by other where.c routines.
 **
 ** where.c:
diff --git a/src/wherecode.c b/src/wherecode.c
index 1a0cdc6d7..5fe230813 100644
--- a/src/wherecode.c
+++ b/src/wherecode.c
@@ -2313,8 +2313,7 @@ Bitmask sqlite3WhereCodeOneLoopStart(
       int nNotReady;                 /* The number of notReady tables */
       SrcItem *origSrc;              /* Original list of tables */
       nNotReady = pWInfo->nLevel - iLevel - 1;
-      pOrTab = sqlite3DbMallocRawNN(db,
-                            sizeof(*pOrTab)+ nNotReady*sizeof(pOrTab->a[0]));
+      pOrTab = sqlite3DbMallocRawNN(db, SZ_SRCLIST(nNotReady+1));
       if( pOrTab==0 ) return notReady;
       pOrTab->nAlloc = (u8)(nNotReady + 1);
       pOrTab->nSrc = pOrTab->nAlloc;
@@ -2857,7 +2856,8 @@ SQLITE_NOINLINE void sqlite3WhereRightJoinLoop(
   WhereInfo *pSubWInfo;
   WhereLoop *pLoop = pLevel->pWLoop;
   SrcItem *pTabItem = &pWInfo->pTabList->a[pLevel->iFrom];
-  SrcList sFrom;
+  SrcList *pFrom;
+  u8 fromSpace[SZ_SRCLIST_1];
   Bitmask mAll = 0;
   int k;
 
@@ -2901,13 +2901,14 @@ SQLITE_NOINLINE void sqlite3WhereRightJoinLoop(
                                  sqlite3ExprDup(pParse->db, pTerm->pExpr, 0));
     }
   }
-  sFrom.nSrc = 1;
-  sFrom.nAlloc = 1;
-  memcpy(&sFrom.a[0], pTabItem, sizeof(SrcItem));
-  sFrom.a[0].fg.jointype = 0;
+  pFrom = (SrcList*)fromSpace;
+  pFrom->nSrc = 1;
+  pFrom->nAlloc = 1;
+  memcpy(&pFrom->a[0], pTabItem, sizeof(SrcItem));
+  pFrom->a[0].fg.jointype = 0;
   assert( pParse->withinRJSubrtn < 100 );
   pParse->withinRJSubrtn++;
-  pSubWInfo = sqlite3WhereBegin(pParse, &sFrom, pSubWhere, 0, 0, 0,
+  pSubWInfo = sqlite3WhereBegin(pParse, pFrom, pSubWhere, 0, 0, 0,
                                 WHERE_RIGHT_JOIN, 0);
   if( pSubWInfo ){
     int iCur = pLevel->iTabCur;