Repository: tursodatabase/libsql (c)

Issue:
`sqlite-vss` fails with libsql
Following works with sqlite but fails with libsql: 

```shell
sqlite> .load ./vector0
sqlite> .load ./vss0

sqlite> select vss_version();
v0.1.2

sqlite> CREATE VIRTUAL TABLE IF NOT EXISTS vss_demo USING vss0(a(2));
sqlite> INSERT INTO vss_demo(rowid, a) VALUES (1, '[1.0, 2.0]'), (2, '[2.0, 2.0]'), (3, '[3.0, 2.0]');

sqlite> SELECT rowid, distance FROM vss_demo WHERE vss_search(a, '[1.0, 2.0]') LIMIT 3;
1|0.0
2|1.0
3|4.0
```

This is the error you get when tried with turso shell:

```
ValueError: Hrana: `stream error: `StreamResponseError { error: Error { message: "SQLite error: SQL logic error" } }``
```

Pull request:
bugfix: reset modifications of `sqlite3_vtab`
fixes #865 

### Cause

Earlier, we had [merged upstream changes](https://github.com/tursodatabase/libsql/pull/625) from SQLite 3.44.0 to libsql. The upstream had modified `sqlite3_module` struct by adding a new field `xIntegrity`. Prior to this, we had added a custom function field `xPreparedSql` to `sqlite3_module`. This change broke the crsqlite extension. 

To fix that, we added a [new struct](https://github.com/tursodatabase/libsql/pull/625#issuecomment-1813954922) `libsql_module` and moved `xPreparedSql` in it. We also added helper functions like `libsql_create_module` and `libsql_create_module_v2`. This change also prompted to modify `sqlite3_vtab` by adding filed pointing to `libsql_module`. This fixed the crsqlite extension.

Unfortunately, it broke sqlite-vss extension. The sqlite-vss extended the `sqlite3_vtab` struct by adding new fields, due to our change, the memory layout assumption changed and caused the issue.

The broken commit: https://github.com/tursodatabase/libsql/commit/e56bdbd52168b0ec96930dac3e9a20523d0eb496, PR of 3.44.0 merge: https://github.com/tursodatabase/libsql/pull/625 (it also has more context and discussion)  

### Fix

I have reversed the `e56bdbd` commit, removed the `libsql_module` struct and the methods we had added. I moved `xPreparedSql` back to `sqlite3_module` and removed the erranous field `libsql_module` from `sqlite3_vtab`. Accordingly, I have modified crsqlite extension as well.

To avoid similar regressions in future, I have added tests for both the extensions. 

Follow up PR: tests for other extensions, add cargo cache to the github workflow, and general speed up tricks



Patch:
diff --git a/libsql-ffi/bundled/src/sqlite3.c b/libsql-ffi/bundled/src/sqlite3.c
index afc329d57a..1b7263d5b3 100644
--- a/libsql-ffi/bundled/src/sqlite3.c
+++ b/libsql-ffi/bundled/src/sqlite3.c
@@ -7658,7 +7658,6 @@ typedef struct sqlite3_vtab sqlite3_vtab;
 typedef struct sqlite3_index_info sqlite3_index_info;
 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
 typedef struct sqlite3_module sqlite3_module;
-typedef struct libsql_module libsql_module;
 
 /*
 ** CAPI3REF: Virtual Table Object
@@ -7716,11 +7715,10 @@ struct sqlite3_module {
   ** Those below are for version 4 and greater. */
   int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema,
                     const char *zTabName, int mFlags, char **pzErr);
-};
 
-/* libSQL extensions for modules */
-struct libsql_module {
-  int iVersion;
+  // reserved for sqlite extension
+  void (*reserved[5])();
+  // following methods are added by libsql
   int (*xPreparedSql)(sqlite3_vtab_cursor*, const char*);
 };
 
@@ -7968,14 +7966,6 @@ SQLITE_API int sqlite3_create_module_v2(
   void *pClientData,         /* Client data for xCreate/xConnect */
   void(*xDestroy)(void*)     /* Module destructor function */
 );
-SQLITE_API int libsql_create_module(
-  sqlite3 *db,                  /* SQLite connection to register module with */
-  const char *zName,            /* Name of the module */
-  const sqlite3_module *p,      /* Methods for the module */
-  const libsql_module *pLibsql, /* Methods for the module */
-  void *pClientData,            /* Client data for xCreate/xConnect */
-  void(*xDestroy)(void*)        /* Module destructor function */
-);
 
 /*
 ** CAPI3REF: Remove Unnecessary Virtual Table Implementations
@@ -8014,7 +8004,6 @@ SQLITE_API int sqlite3_drop_modules(
 */
 struct sqlite3_vtab {
   const sqlite3_module *pModule;      /* The module for this virtual table */
-  const libsql_module *pLibsqlModule; /* The libSQL module for this virtual table */
   int nRef;                           /* Number of open cursors */
   char *zErrMsg;                      /* Error message from sqlite3_mprintf() */
   /* Virtual table implementations will typically add additional fields */
@@ -18561,7 +18550,6 @@ struct Savepoint {
 */
 struct Module {
   const sqlite3_module *pModule;       /* Callback pointers */
-  const libsql_module *pLibsqlModule;  /* Callback pointers for libSQL */
   const char *zName;                   /* Name passed to create_module() */
   int nRefModule;                      /* Number of pointers to this object */
   void *pAux;                          /* pAux passed to create_module() */
@@ -21836,7 +21824,6 @@ SQLITE_PRIVATE    Module *sqlite3VtabCreateModule(
      sqlite3*,
      const char*,
      const sqlite3_module*,
-     const libsql_module*,
      void*,
      void(*)(void*)
    );
@@ -101258,7 +101245,6 @@ case OP_VInitIn: {        /* out2, ncycle */
 */
 case OP_VPreparedSql: {
   const sqlite3_module *pModule;
-  const libsql_module *pLibsqlModule;
   sqlite3_vtab_cursor *pVCur;
   sqlite3_vtab *pVtab;
   VdbeCursor *pCur;
@@ -101269,14 +101255,13 @@ case OP_VPreparedSql: {
   pVCur = pCur->uc.pVCur;
   pVtab = pVCur->pVtab;
   pModule = pVtab->pModule;
-  pLibsqlModule = pVtab->pLibsqlModule;
 
   /* Invoke the xPreparedSql method */
-   if (pLibsqlModule) {
-    if( pLibsqlModule->xPreparedSql && p->zSql ){
-      rc = pLibsqlModule->xPreparedSql(pVCur, p->zSql);
-      if( rc ) goto abort_due_to_error;
-    }
+  if( pModule->iVersion>=700 ) {
+      if (pModule->xPreparedSql && p->zSql) {
+          rc = pModule->xPreparedSql(pVCur, p->zSql);
+          if (rc) goto abort_due_to_error;
+      }
   }
 
   break;
@@ -141651,7 +141636,7 @@ SQLITE_PRIVATE Module *sqlite3PragmaVtabRegister(sqlite3 *db, const char *zName)
   if( pName==0 ) return 0;
   if( (pName->mPragFlg & (PragFlg_Result0|PragFlg_Result1))==0 ) return 0;
   assert( sqlite3HashFind(&db->aModule, zName)==0 );
-  return sqlite3VtabCreateModule(db, zName, &pragmaVtabModule, NULL, (void*)pName, 0);
+  return sqlite3VtabCreateModule(db, zName, &pragmaVtabModule, (void*)pName, 0);
 }
 
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
@@ -155133,7 +155118,6 @@ SQLITE_PRIVATE Module *sqlite3VtabCreateModule(
   sqlite3 *db,                        /* Database in which module is registered */
   const char *zName,                  /* Name assigned to this module */
   const sqlite3_module *pModule,      /* The definition of the module */
-  const libsql_module *pLibsqlModule, /* The definition of the libSQL module */
   void *pAux,                         /* Context pointer for xCreate/xConnect */
   void (*xDestroy)(void *)            /* Module destructor function */
 ){
@@ -155154,7 +155138,6 @@ SQLITE_PRIVATE Module *sqlite3VtabCreateModule(
     memcpy(zCopy, zName, nName+1);
     pMod->zName = zCopy;
     pMod->pModule = pModule;
-    pMod->pLibsqlModule = pLibsqlModule;
     pMod->pAux = pAux;
     pMod->xDestroy = xDestroy;
     pMod->pEpoTab = 0;
@@ -155183,14 +155166,13 @@ static int createModule(
   sqlite3 *db,                        /* Database in which module is registered */
   const char *zName,                  /* Name assigned to this module */
   const sqlite3_module *pModule,      /* The definition of the module */
-  const libsql_module *pLibsqlModule, /* The definition of the libSQL module */
   void *pAux,                         /* Context pointer for xCreate/xConnect */
   void (*xDestroy)(void *)            /* Module destructor function */
 ){
   int rc = SQLITE_OK;
 
   sqlite3_mutex_enter(db->mutex);
-  (void)sqlite3VtabCreateModule(db, zName, pModule, pLibsqlModule, pAux, xDestroy);
+  (void)sqlite3VtabCreateModule(db, zName, pModule, pAux, xDestroy);
   rc = sqlite3ApiExit(db, rc);
   if( rc!=SQLITE_OK && xDestroy ) xDestroy(pAux);
   sqlite3_mutex_leave(db->mutex);
@@ -155210,7 +155192,7 @@ SQLITE_API int sqlite3_create_module(
 #ifdef SQLITE_ENABLE_API_ARMOR
   if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
 #endif
-  return createModule(db, zName, pModule, NULL, pAux, 0);
+  return createModule(db, zName, pModule, pAux, 0);
 }
 
 /*
@@ -155226,24 +155208,7 @@ SQLITE_API int sqlite3_create_module_v2(
 #ifdef SQLITE_ENABLE_API_ARMOR
   if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
 #endif
-  return createModule(db, zName, pModule, NULL, pAux, xDestroy);
-}
-
-/*
-** External API function used to create a new virtual-table module.
-*/
-int libsql_create_module_v2(
-  sqlite3 *db,                         /* Database in which module is registered */
-  const char *zName,                   /* Name assigned to this module */
-  const sqlite3_module *pModule,       /* The definition of the module */
-  const libsql_module *pLibsqlModule,  /* The definition of the module */
-  void *pAux,                          /* Context pointer for xCreate/xConnect */
-  void (*xDestroy)(void *)             /* Module destructor function */
-){
-#ifdef SQLITE_ENABLE_API_ARMOR
-  if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
-#endif
-  return createModule(db, zName, pModule, pLibsqlModule, pAux, xDestroy);
+  return createModule(db, zName, pModule, pAux, xDestroy);
 }
 
 /*
@@ -155263,7 +155228,7 @@ SQLITE_API int sqlite3_drop_modules(sqlite3 *db, const char** azNames){
       for(ii=0; azNames[ii]!=0 && strcmp(azNames[ii],pMod->zName)!=0; ii++){}
       if( azNames[ii]!=0 ) continue;
     }
-    createModule(db, pMod->zName, 0, 0, 0, 0);
+    createModule(db, pMod->zName, 0, 0, 0);
   }
   return SQLITE_OK;
 }
@@ -155743,7 +155708,6 @@ static int vtabCallConstructor(
     ** the sqlite3_vtab object if successful.  */
     memset(pVTable->pVtab, 0, sizeof(pVTable->pVtab[0]));
     pVTable->pVtab->pModule = pMod->pModule;
-    pVTable->pVtab->pLibsqlModule = pMod->pLibsqlModule;
     pMod->nRefModule++;
     pVTable->nRef = 1;
     if( sCtx.bDeclared==0 ){
diff --git a/libsql-ffi/bundled/src/sqlite3.h b/libsql-ffi/bundled/src/sqlite3.h
index 8ae944a887..2940a5ed30 100644
--- a/libsql-ffi/bundled/src/sqlite3.h
+++ b/libsql-ffi/bundled/src/sqlite3.h
@@ -7284,7 +7284,6 @@ typedef struct sqlite3_vtab sqlite3_vtab;
 typedef struct sqlite3_index_info sqlite3_index_info;
 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
 typedef struct sqlite3_module sqlite3_module;
-typedef struct libsql_module libsql_module;
 
 /*
 ** CAPI3REF: Virtual Table Object
@@ -7342,11 +7341,10 @@ struct sqlite3_module {
   ** Those below are for version 4 and greater. */
   int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema,
                     const char *zTabName, int mFlags, char **pzErr);
-};
 
-/* libSQL extensions for modules */
-struct libsql_module {
-  int iVersion;
+  // reserved for sqlite extension
+  void (*reserved[5])();
+  // following methods are added by libsql
   int (*xPreparedSql)(sqlite3_vtab_cursor*, const char*);
 };
 
@@ -7594,14 +7592,6 @@ SQLITE_API int sqlite3_create_module_v2(
   void *pClientData,         /* Client data for xCreate/xConnect */
   void(*xDestroy)(void*)     /* Module destructor function */
 );
-SQLITE_API int libsql_create_module(
-  sqlite3 *db,                  /* SQLite connection to register module with */
-  const char *zName,            /* Name of the module */
-  const sqlite3_module *p,      /* Methods for the module */
-  const libsql_module *pLibsql, /* Methods for the module */
-  void *pClientData,            /* Client data for xCreate/xConnect */
-  void(*xDestroy)(void*)        /* Module destructor function */
-);
 
 /*
 ** CAPI3REF: Remove Unnecessary Virtual Table Implementations
@@ -7640,7 +7630,6 @@ SQLITE_API int sqlite3_drop_modules(
 */
 struct sqlite3_vtab {
   const sqlite3_module *pModule;      /* The module for this virtual table */
-  const libsql_module *pLibsqlModule; /* The libSQL module for this virtual table */
   int nRef;                           /* Number of open cursors */
   char *zErrMsg;                      /* Error message from sqlite3_mprintf() */
   /* Virtual table implementations will typically add additional fields */
diff --git a/libsql-sqlite3/ext/crr/rs/core/src/create_cl_set_vtab.rs b/libsql-sqlite3/ext/crr/rs/core/src/create_cl_set_vtab.rs
index 34fd16839b..649cbafab0 100644
--- a/libsql-sqlite3/ext/crr/rs/core/src/create_cl_set_vtab.rs
+++ b/libsql-sqlite3/ext/crr/rs/core/src/create_cl_set_vtab.rs
@@ -140,8 +140,6 @@ fn connect_create_shared(
             nRef: 0,
             pModule: core::ptr::null(),
             zErrMsg: core::ptr::null_mut(),
-            #[cfg(feature = "libsql")]
-            pLibsqlModule: core::ptr::null_mut(),
         },
         base_table_name: base_name_from_virtual_name(args.table_name).to_owned(),
         db_name: args.database_name.to_owned(),
@@ -259,6 +257,8 @@ static MODULE: sqlite_nostd::module = sqlite_nostd::module {
     xRollbackTo: None,
     xShadowName: None,
     xIntegrity: None,
+    reserved: [None, None, None, None, None],
+    xPreparedSql: None,
 };
 
 pub fn create_module(db: *mut sqlite::sqlite3) -> Result<ResultCode, ResultCode> {
diff --git a/libsql-sqlite3/ext/crr/rs/core/src/unpack_columns_vtab.rs b/libsql-sqlite3/ext/crr/rs/core/src/unpack_columns_vtab.rs
index 036b419b00..bb12781a46 100644
--- a/libsql-sqlite3/ext/crr/rs/core/src/unpack_columns_vtab.rs
+++ b/libsql-sqlite3/ext/crr/rs/core/src/unpack_columns_vtab.rs
@@ -38,8 +38,6 @@ extern "C" fn connect(
             nRef: 0,
             pModule: core::ptr::null(),
             zErrMsg: core::ptr::null_mut(),
-            #[cfg(feature = "libsql")]
-            pLibsqlModule: core::ptr::null_mut(),
         }));
         let _ = sqlite::vtab_config(db, sqlite::INNOCUOUS);
     }
@@ -256,6 +254,8 @@ static MODULE: sqlite_nostd::module = sqlite_nostd::module {
     xRollbackTo: None,
     xShadowName: None,
     xIntegrity: None,
+    reserved: [None, None, None, None, None],
+    xPreparedSql: None,
 };
 
 /**
diff --git a/libsql-sqlite3/ext/crr/src/changes-vtab.c b/libsql-sqlite3/ext/crr/src/changes-vtab.c
index 923f683918..e1815c49df 100644
--- a/libsql-sqlite3/ext/crr/src/changes-vtab.c
+++ b/libsql-sqlite3/ext/crr/src/changes-vtab.c
@@ -179,6 +179,7 @@ sqlite3_module crsql_changesModule = {
     /* xShadowName */ 0
 #ifdef LIBSQL
     ,
+    /* reserved */ NULL,
     /* xPreparedSql */ 0
 #endif
 };
diff --git a/libsql-sqlite3/src/pragma.c b/libsql-sqlite3/src/pragma.c
index 69367dd680..bd5d95085d 100644
--- a/libsql-sqlite3/src/pragma.c
+++ b/libsql-sqlite3/src/pragma.c
@@ -2936,7 +2936,7 @@ Module *sqlite3PragmaVtabRegister(sqlite3 *db, const char *zName){
   if( pName==0 ) return 0;
   if( (pName->mPragFlg & (PragFlg_Result0|PragFlg_Result1))==0 ) return 0;
   assert( sqlite3HashFind(&db->aModule, zName)==0 );
-  return sqlite3VtabCreateModule(db, zName, &pragmaVtabModule, NULL, (void*)pName, 0);
+  return sqlite3VtabCreateModule(db, zName, &pragmaVtabModule, (void*)pName, 0);
 }
 
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
diff --git a/libsql-sqlite3/src/sqlite.h.in b/libsql-sqlite3/src/sqlite.h.in
index 67625ba6c8..c336d235d3 100644
--- a/libsql-sqlite3/src/sqlite.h.in
+++ b/libsql-sqlite3/src/sqlite.h.in
@@ -7284,7 +7284,6 @@ typedef struct sqlite3_vtab sqlite3_vtab;
 typedef struct sqlite3_index_info sqlite3_index_info;
 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
 typedef struct sqlite3_module sqlite3_module;
-typedef struct libsql_module libsql_module;
 
 /*
 ** CAPI3REF: Virtual Table Object
@@ -7342,11 +7341,10 @@ struct sqlite3_module {
   ** Those below are for version 4 and greater. */
   int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema,
                     const char *zTabName, int mFlags, char **pzErr);
-};
 
-/* libSQL extensions for modules */
-struct libsql_module {
-  int iVersion;
+  // reserved for sqlite extension
+  void (*reserved[5])();
+  // following methods are added by libsql
   int (*xPreparedSql)(sqlite3_vtab_cursor*, const char*);
 };
 
@@ -7594,14 +7592,6 @@ int sqlite3_create_module_v2(
   void *pClientData,         /* Client data for xCreate/xConnect */
   void(*xDestroy)(void*)     /* Module destructor function */
 );
-int libsql_create_module(
-  sqlite3 *db,                  /* SQLite connection to register module with */
-  const char *zName,            /* Name of the module */
-  const sqlite3_module *p,      /* Methods for the module */
-  const libsql_module *pLibsql, /* Methods for the module */
-  void *pClientData,            /* Client data for xCreate/xConnect */
-  void(*xDestroy)(void*)        /* Module destructor function */
-);
 
 /*
 ** CAPI3REF: Remove Unnecessary Virtual Table Implementations
@@ -7640,7 +7630,6 @@ int sqlite3_drop_modules(
 */
 struct sqlite3_vtab {
   const sqlite3_module *pModule;      /* The module for this virtual table */
-  const libsql_module *pLibsqlModule; /* The libSQL module for this virtual table */
   int nRef;                           /* Number of open cursors */
   char *zErrMsg;                      /* Error message from sqlite3_mprintf() */
   /* Virtual table implementations will typically add additional fields */
diff --git a/libsql-sqlite3/src/sqliteInt.h b/libsql-sqlite3/src/sqliteInt.h
index 0bde8546a6..455d221476 100644
--- a/libsql-sqlite3/src/sqliteInt.h
+++ b/libsql-sqlite3/src/sqliteInt.h
@@ -2200,7 +2200,6 @@ struct Savepoint {
 */
 struct Module {
   const sqlite3_module *pModule;       /* Callback pointers */
-  const libsql_module *pLibsqlModule;  /* Callback pointers for libSQL */
   const char *zName;                   /* Name passed to create_module() */
   int nRefModule;                      /* Number of pointers to this object */
   void *pAux;                          /* pAux passed to create_module() */
@@ -5475,7 +5474,6 @@ void sqlite3AutoLoadExtensions(sqlite3*);
      sqlite3*,
      const char*,
      const sqlite3_module*,
-     const libsql_module*,
      void*,
      void(*)(void*)
    );
diff --git a/libsql-sqlite3/src/vdbe.c b/libsql-sqlite3/src/vdbe.c
index 01a3e5a6f1..e3e7dbb094 100644
--- a/libsql-sqlite3/src/vdbe.c
+++ b/libsql-sqlite3/src/vdbe.c
@@ -8309,7 +8309,6 @@ case OP_VInitIn: {        /* out2, ncycle */
 */
 case OP_VPreparedSql: {
   const sqlite3_module *pModule;
-  const libsql_module *pLibsqlModule;
   sqlite3_vtab_cursor *pVCur;
   sqlite3_vtab *pVtab;
   VdbeCursor *pCur;
@@ -8320,14 +8319,13 @@ case OP_VPreparedSql: {
   pVCur = pCur->uc.pVCur;
   pVtab = pVCur->pVtab;
   pModule = pVtab->pModule;
-  pLibsqlModule = pVtab->pLibsqlModule;
 
   /* Invoke the xPreparedSql method */
-   if (pLibsqlModule) {
-    if( pLibsqlModule->xPreparedSql && p->zSql ){
-      rc = pLibsqlModule->xPreparedSql(pVCur, p->zSql);
-      if( rc ) goto abort_due_to_error;
-    }
+  if( pModule->iVersion>=700 ) {
+      if (pModule->xPreparedSql && p->zSql) {
+          rc = pModule->xPreparedSql(pVCur, p->zSql);
+          if (rc) goto abort_due_to_error;
+      }
   }
 
   break;
diff --git a/libsql-sqlite3/src/vtab.c b/libsql-sqlite3/src/vtab.c
index fa21589726..1dd3494a40 100644
--- a/libsql-sqlite3/src/vtab.c
+++ b/libsql-sqlite3/src/vtab.c
@@ -40,7 +40,6 @@ Module *sqlite3VtabCreateModule(
   sqlite3 *db,                        /* Database in which module is registered */
   const char *zName,                  /* Name assigned to this module */
   const sqlite3_module *pModule,      /* The definition of the module */
-  const libsql_module *pLibsqlModule, /* The definition of the libSQL module */
   void *pAux,                         /* Context pointer for xCreate/xConnect */
   void (*xDestroy)(void *)            /* Module destructor function */
 ){
@@ -61,7 +60,6 @@ Module *sqlite3VtabCreateModule(
     memcpy(zCopy, zName, nName+1);
     pMod->zName = zCopy;
     pMod->pModule = pModule;
-    pMod->pLibsqlModule = pLibsqlModule;
     pMod->pAux = pAux;
     pMod->xDestroy = xDestroy;
     pMod->pEpoTab = 0;
@@ -90,14 +88,13 @@ static int createModule(
   sqlite3 *db,                        /* Database in which module is registered */
   const char *zName,                  /* Name assigned to this module */
   const sqlite3_module *pModule,      /* The definition of the module */
-  const libsql_module *pLibsqlModule, /* The definition of the libSQL module */
   void *pAux,                         /* Context pointer for xCreate/xConnect */
   void (*xDestroy)(void *)            /* Module destructor function */
 ){
   int rc = SQLITE_OK;
 
   sqlite3_mutex_enter(db->mutex);
-  (void)sqlite3VtabCreateModule(db, zName, pModule, pLibsqlModule, pAux, xDestroy);
+  (void)sqlite3VtabCreateModule(db, zName, pModule, pAux, xDestroy);
   rc = sqlite3ApiExit(db, rc);
   if( rc!=SQLITE_OK && xDestroy ) xDestroy(pAux);
   sqlite3_mutex_leave(db->mutex);
@@ -117,7 +114,7 @@ int sqlite3_create_module(
 #ifdef SQLITE_ENABLE_API_ARMOR
   if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
 #endif
-  return createModule(db, zName, pModule, NULL, pAux, 0);
+  return createModule(db, zName, pModule, pAux, 0);
 }
 
 /*
@@ -133,24 +130,7 @@ int sqlite3_create_module_v2(
 #ifdef SQLITE_ENABLE_API_ARMOR
   if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
 #endif
-  return createModule(db, zName, pModule, NULL, pAux, xDestroy);
-}
-
-/*
-** External API function used to create a new virtual-table module.
-*/
-int libsql_create_module_v2(
-  sqlite3 *db,                         /* Database in which module is registered */
-  const char *zName,                   /* Name assigned to this module */
-  const sqlite3_module *pModule,       /* The definition of the module */
-  const libsql_module *pLibsqlModule,  /* The definition of the module */
-  void *pAux,                          /* Context pointer for xCreate/xConnect */
-  void (*xDestroy)(void *)             /* Module destructor function */
-){
-#ifdef SQLITE_ENABLE_API_ARMOR
-  if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
-#endif
-  return createModule(db, zName, pModule, pLibsqlModule, pAux, xDestroy);
+  return createModule(db, zName, pModule, pAux, xDestroy);
 }
 
 /*
@@ -170,7 +150,7 @@ int sqlite3_drop_modules(sqlite3 *db, const char** azNames){
       for(ii=0; azNames[ii]!=0 && strcmp(azNames[ii],pMod->zName)!=0; ii++){}
       if( azNames[ii]!=0 ) continue;
     }
-    createModule(db, pMod->zName, 0, 0, 0, 0);
+    createModule(db, pMod->zName, 0, 0, 0);
   }
   return SQLITE_OK;
 }
@@ -650,7 +630,6 @@ static int vtabCallConstructor(
     ** the sqlite3_vtab object if successful.  */
     memset(pVTable->pVtab, 0, sizeof(pVTable->pVtab[0]));
     pVTable->pVtab->pModule = pMod->pModule;
-    pVTable->pVtab->pLibsqlModule = pMod->pLibsqlModule;
     pMod->nRefModule++;
     pVTable->nRef = 1;
     if( sCtx.bDeclared==0 ){


Test patch:
diff --git a/.github/workflows/extensions-test.yml b/.github/workflows/extensions-test.yml
new file mode 100644
index 0000000000..5477a194b8
--- /dev/null
+++ b/.github/workflows/extensions-test.yml
@@ -0,0 +1,79 @@
+name: Extensions Tests
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+  merge_group:
+    branches: [ "main" ]
+
+env:
+  CARGO_TERM_COLOR: always
+  PROTOC_VERSION: 3.23.4
+
+jobs:
+  c-tests:
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: libsql-sqlite3
+    name: CR SQLite C Tests
+
+    steps:
+      - uses: hecrj/setup-rust-action@v1
+      - name: Checkout repository
+        uses: actions/checkout@v3
+      - name: build libsql
+        run: |
+          ./configure
+          make libsql
+      - name: build
+        run: |
+          cd ext/crr
+          make loadable
+      - name: test
+        run: |
+          cd ext/crr
+          make test
+
+  rs-tests:
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: libsql-sqlite3
+    name: CR SQLite Rust Tests
+
+    steps:
+      - uses: hecrj/setup-rust-action@v1
+      - name: Checkout repository
+        uses: actions/checkout@v3
+      - name: build libsql
+        run: |
+          ./configure
+          make libsql
+      - name: test
+        run: |
+          cd ext/crr/rs/core
+          cargo test --features=loadable_extension
+
+  extensions-tests:
+    runs-on: ubuntu-latest
+    name: Extensions Tests
+
+    steps:
+      - uses: hecrj/setup-rust-action@v1
+      - name: Checkout repository
+        uses: actions/checkout@v3
+      - name: build libsql and ffi bindings
+        run: |
+          cargo xtask build-bundled
+      - name: download extensions
+        run: |
+          cd libsql-sqlite3/test/rust_suite
+          export VSS_VERSION="v0.1.2"
+          wget https://github.com/asg017/sqlite-vss/releases/download/$VSS_VERSION/sqlite-vss-$VSS_VERSION-loadable-linux-x86_64.tar.gz
+          tar -xvf sqlite-vss-$VSS_VERSION-loadable-linux-x86_64.tar.gz -C src
+      - name: test
+        run: |
+          cd libsql-sqlite3/test/rust_suite
+          cargo test --features extensions
\ No newline at end of file
diff --git a/libsql-sqlite3/test/rust_suite/Cargo.toml b/libsql-sqlite3/test/rust_suite/Cargo.toml
index 6c2425d1c4..6a557d23a6 100644
--- a/libsql-sqlite3/test/rust_suite/Cargo.toml
+++ b/libsql-sqlite3/test/rust_suite/Cargo.toml
@@ -19,4 +19,5 @@ hex = "0.4.3"
 default = []
 udf = []
 wasm = []
+extensions = []
 full = ["udf", "wasm"]
diff --git a/libsql-sqlite3/test/rust_suite/src/extensions.rs b/libsql-sqlite3/test/rust_suite/src/extensions.rs
new file mode 100644
index 0000000000..02defdca2d
--- /dev/null
+++ b/libsql-sqlite3/test/rust_suite/src/extensions.rs
@@ -0,0 +1,18 @@
+use libsql_sys::rusqlite::{Connection, params, LoadExtensionGuard};
+
+#[test]
+fn test_sqlite_vss() {
+    let conn = Connection::open_in_memory().unwrap();
+    unsafe {
+        let _guard = LoadExtensionGuard::new(&conn).unwrap();
+        conn.load_extension("src/vector0", None).unwrap();
+        conn.load_extension("src/vss0", None).unwrap();
+    }
+    conn.execute("CREATE VIRTUAL TABLE IF NOT EXISTS vss_demo USING vss0(a(2))", ())
+        .unwrap();
+    conn.execute("INSERT INTO vss_demo(rowid, a) VALUES (1, '[1.0, 2.0]'), (2, '[2.0, 2.0]'), (3, '[3.0, 2.0]')", ()).unwrap();
+    conn.execute(
+        "SELECT rowid, distance FROM vss_demo WHERE vss_search(?, ?) LIMIT 3",
+        params![1.0, 2.0],
+    ).unwrap();
+}
\ No newline at end of file
diff --git a/libsql-sqlite3/test/rust_suite/src/lib.rs b/libsql-sqlite3/test/rust_suite/src/lib.rs
index b8ba21365d..92c9b58399 100644
--- a/libsql-sqlite3/test/rust_suite/src/lib.rs
+++ b/libsql-sqlite3/test/rust_suite/src/lib.rs
@@ -2,6 +2,8 @@
 mod alter_column;
 mod random_rowid;
 mod virtual_wal;
+#[cfg(all(test, feature = "extensions"))]
+mod extensions;
 
 #[cfg(all(test, feature = "udf"))]
 mod user_defined_functions;