Backport SQLite memcmp patch.

third_party/sqlite/amalgamation/sqlite3.c

Index: third_party/sqlite/amalgamation/sqlite3.c
diff --git a/third_party/sqlite/amalgamation/sqlite3.c b/third_party/sqlite/amalgamation/sqlite3.c
index b9088a522a4a147600ce3db65ef7870c10be6e73..247d842c225db15937989c5aceb8ac51e0b99d33 100644
--- a/third_party/sqlite/amalgamation/sqlite3.c
+++ b/third_party/sqlite/amalgamation/sqlite3.c
@@ -28651,7 +28651,7 @@ int fillInUnixFile(
   OSTRACE(("OPEN    %-3d %s\n", h, zFilename));
   pNew->h = h;
   pNew->zPath = zFilename;
-  if( memcmp(pVfs->zName,"unix-excl",10)==0 ){
+  if( strcmp(pVfs->zName,"unix-excl")==0 ){
     pNew->ctrlFlags = UNIXFILE_EXCL;
   }else{
     pNew->ctrlFlags = 0;
@@ -61676,7 +61676,7 @@ SQLITE_PRIVATE int sqlite3VdbeParameterIndex(Vdbe *p, const char *zName, int nNa
   if( zName ){
     for(i=0; i<p->nVar; i++){
       const char *z = p->azVar[i];
-      if( z && memcmp(z,zName,nName)==0 && z[nName]==0 ){
+      if( z && strncmp(z,zName,nName)==0 && z[nName]==0 ){
         return i+1;
       }
     }
@@ -71435,12 +71435,10 @@ SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
     ** has never appeared before, reuse the same variable number
     */
     int i;
-    u32 n;
-    n = sqlite3Strlen30(z);
     for(i=0; i<pParse->nVarExpr; i++){
       Expr *pE = pParse->apVarExpr[i];
       assert( pE!=0 );
-      if( memcmp(pE->u.zToken, z, n)==0 && pE->u.zToken[n]==0 ){
+      if( strcmp(pE->u.zToken, z)==0 ){
         pExpr->iColumn = pE->iColumn;
         break;
       }
@@ -75586,7 +75584,7 @@ static void analyzeOneTable(
     /* Do not gather statistics on views or virtual tables */
     return;
   }
-  if( memcmp(pTab->zName, "sqlite_", 7)==0 ){
+  if( sqlite3_strnicmp(pTab->zName, "sqlite_", 7)==0 ){
     /* Do not gather statistics on system tables */
     return;
   }
@@ -75992,7 +75990,7 @@ static int analysisLoader(void *pData, int argc, char **argv, char **NotUsed){
     if( pIndex==0 ) break;
     pIndex->aiRowEst[i] = v;
     if( *z==' ' ) z++;
-    if( memcmp(z, "unordered", 10)==0 ){
+    if( strcmp(z, "unordered")==0 ){
       pIndex->bUnordered = 1;
       break;
     }
@@ -79439,7 +79437,7 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
   assert( pTab!=0 );
   assert( pParse->nErr==0 );
   if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 
-       && memcmp(&pTab->zName[7],"altertab_",9)!=0 ){
+       && sqlite3StrNICmp(&pTab->zName[7],"altertab_",9)!=0 ){
     sqlite3ErrorMsg(pParse, "table %s may not be indexed", pTab->zName);
     goto exit_create_index;
   }